A tram (in North America streetcar or trolley) is a rail vehicle that runs on tramway tracks along public urban streets; some include segments of segregated right-of-way.^[1][2] The lines or networks operated by tramcars are called tramways. Historically the term electric street railways was also used in the United States. In the United States, the term tram has sometimes been used for rubber-tired trackless trains, which are unrelated to other kinds of trams.

Tram vehicles are usually lighter and shorter than main line and rapid transit trains. Today, most trams use electrical power, usually fed by a pantograph sliding on an overhead line; older systems may use a trolley pole or a bow collector. In some cases by a contact shoe on a third rail is used. If necessary, they may have dual power systems—electricity in city streets, and diesel in more rural environments. Occasionally, trams also carry freight.

Trams are now commonly included in the wider term "light rail",^[3] which also includes grade-separated systems. Some trams, known as tram-trains, may have segments that run on mainline railway tracks, similar to interurban systems. The differences between these modes of rail transport are often indistinct, and a given system may combine multiple features.

One of the advantages over earlier forms of transit was the low rolling resistance of metal wheels on steel rails, allowing the trams to haul a greater load for a given effort. Problems included the fact that any given animal could only work so many hours on a given day, had to be housed, groomed, fed and cared for day in and day out, and produced prodigious amounts of manure, which the streetcar company was charged with disposing of. Electric trams largely replaced animal power in the late 19th and early 20th century. Improvements in other forms of road transport such as buses led to decline of trams in the mid 20th century. Trams have seen resurgence in recent years.

The English terms tram and tramway are derived from the Scots word tram,^[4] referring respectively to a type of truck (goods wagon or freight railroad car) used in coal mines and the tracks on which they ran. The word tram probably derived from Middle Flemish trame ("beam, handle of a barrow, bar, rung"). The identical word la trame with the meaning "crossbeam" is also used in the French language. Etymologists believe that the word tram refers to the wooden beams the railway tracks were initially made of before the railroad pioneers switched to the much more wear-resistant tracks made of iron and, later, steel.^[5] The word Tram-car is attested from 1873.^[6]

Although the terms tram and tramway have been adopted by many languages, they are not used universally in English; North Americans prefer streetcar, trolley, or trolleycar. The term streetcar is first recorded in 1840, and originally referred to horsecars. When electrification came, Americans began to speak of trolleycars or later, trolleys. A widely held belief holds the word to derive from the troller (said to derive from the words traveler and roller), a four-wheeled device that was dragged along dual overhead wires by a cable that connected the troller to the top of the car and collected electrical power from the overhead wires;^[7] this portmanteau derivation is, however, most likely folk etymology. "Trolley" and variants refer to the verb troll, meaning "roll" and probably derived from Old French,^[8] and cognate uses of the word were well established for handcarts and horse drayage, as well as for nautical uses.^[9]

The alternative North American term 'trolley' may strictly speaking be considered incorrect, as the term can also be applied to cable cars, or conduit cars that instead draw power from an underground supply. Conventional diesel tourist buses decorated to look like streetcars are sometimes called trolleys in the US (tourist trolley). Furthering confusion, the term tram has instead been applied to open-sided, low-speed segmented vehicles on rubber tires generally used to ferry tourists short distances, for example on the Universal Studios backlot tour and, in many countries, as tourist transport to major destinations. The term may also apply to an aerial ropeway, e.g. the Roosevelt Island Tramway.

Although the use of the term trolley for tram was not adopted in Europe, the term was later associated with the trolleybus, a rubber-tyred vehicle running on hard pavement, which draws its power from pairs of overhead wires. These electric buses, which use twin trolley poles, are also called trackless trolleys (particularly in the northeastern US), or sometimes simply trolleys (in the UK, as well as the Pacific Northwest, including Seattle, and Vancouver).

The New South Wales, Australia, government has decided to use the term "light rail" for their trams.

The history of trams, streetcars or trolley systems, began in the early nineteenth century.

It can be divided up into several discrete periods defined by the principal means of motive power used.

The world's first passenger train or tram was the Swansea and Mumbles Railway, in Wales, UK. The Mumbles Railway Act was passed by the British Parliament in 1804, and horse-drawn service started in 1807.^[10] The service closed in 1827, but was restarted in 1860, again using horses.^[11] It was worked by steam from 1877, and then, from 1929, by very large (106-seater) electric tramcars, until closure in 1961. The Swansea and Mumbles Railway was something of a one-off however, and no street tramway would appear in Britain until 1860 when one was built in Birkenhead by the American George Francis Train.^[12]

Street railways developed in America before Europe, largely due to the poor paving of the streets in American cities which made them unsuitable for horsebuses, which were then common on the well-paved streets of European cities. Running the horsecars on rails allowed for a much smoother ride. There are records of a street railway running in Baltimore as early as 1828, however the first authenticated streetcar in America, was the New York and Harlem Railroad developed by the Irish coach builder John Stephenson, in New York City which began service in the year 1832.^[13][14] The New York and Harlem Railroad's Fourth Avenue Line ran along the Bowery and Fourth Avenue in New York City. It was followed in 1835 by the New Orleans and Carrollton Railroad in New Orleans, Louisiana,^[15] which still operates as the St. Charles Streetcar Line. Other American cities did not follow until the 1850s, after which the "animal railway" became an increasingly common feature in the larger towns.^[15]

The first permanent tram line in continental Europe was opened in Paris in 1855 by Alphonse Loubat who had previously worked on American streetcar lines.^[16] The tram was developed in numerous cities of Europe (some of the most extensive systems were found in Berlin, Budapest, Birmingham, Leningrad, Lisbon, London, Manchester, Paris).

The first tram in South America opened in 1858 in Santiago, Chile. The first trams in Australia opened in 1860 in Sydney. Africa's first tram service started in Alexandria on 8 January 1863. The first trams in Asia opened in 1869 in Batavia (now Jakarta), Netherlands East Indies (now Indonesia).

Problems with horsecars included the fact that any given animal could only work so many hours on a given day, had to be housed, groomed, fed and cared for day in and day out, and produced prodigious amounts of manure, which the streetcar company was charged with storing and then disposing of.

Since a typical horse pulled a streetcar for about a dozen miles a day and worked for four or five hours, many systems needed ten or more horses in stable for each horsecar.

Horsecars were largely replaced by electric-powered trams following the improvement of an overhead trolley system on trams for collecting electricity from overhead wires by Frank J. Sprague. His spring-loaded trolley pole used a wheel to travel along the wire. In late 1887 and early 1888, using his trolley system, Sprague installed the first successful large electric street railway system in Richmond, Virginia. Within a year, the economy of electric power had replaced more costly horsecars in many cities. By 1889, 110 electric railways incorporating Sprague's equipment had been begun or planned on several continents.^[17]

Horses continued to be used for light shunting well into the 20th century, and many large metropolitan lines lasted into the early 20th century.

New York City had a regular horsecar service on the Bleecker Street Line until its closure in 1917.^[18] Pittsburgh, Pennsylvania, had its Sarah Street line drawn by horses until 1923. The last regular mule-drawn cars in the US ran in Sulphur Rock, Arkansas, until 1926 and were commemorated by a U.S. postage stamp issued in 1983.^[19] The last mule tram service in Mexico City ended in 1932, and a mule tram in Celaya, Mexico, survived until 1954.^[20] The last horse-drawn tram to be withdrawn from public service in the UK took passengers from Fintona railway station to Fintona Junction one mile away on the main Omagh to Enniskillen railway in Northern Ireland. The tram made its last journey on 30 September 1957 when the Omagh to Enniskillen line closed. The "van" now lies at the Ulster Transport Museum.

Horse-drawn trams still operate on the 1876-built Douglas Bay Horse Tramway in the Isle of Man, and at the 1894-built horse tram at Victor Harbor in South Australia. New horse-drawn systems have been established at the Hokkaidō Museum in Japan and also in Disneyland. A horse tram route in Polish gmina Mrozy, first built in 1902, was reopened in 2012.

The first mechanical trams were powered by steam. Generally, there were two types of steam tram. The first and most common had a small steam locomotive (called a tram engine in the UK) at the head of a line of one or more carriages, similar to a small train. Systems with such steam trams included Christchurch, New Zealand; Sydney, Australia; other city systems in New South Wales; Munich, Germany (from August 1883 on),^[21] British India (Pakistan) (from 1885) and the Dublin & Blessington Steam Tramway (from 1888) in Ireland. Steam tramways also were used on the suburban tramway lines around Milan and Padua; the last Gamba de Legn ("Peg-Leg") tramway ran on the Milan-Magenta-Castano Primo route in late 1957.^[22]

The other style of steam tram had the steam engine in the body of the tram, referred to as a tram engine (UK) or steam dummy (US). The most notable system to adopt such trams was in Paris. French-designed steam trams also operated in Rockhampton, in the Australian state of Queensland between 1909 and 1939. Stockholm, Sweden, had a steam tram line at the island of Södermalm between 1887 and 1901.

Tram engines usually had modifications to make them suitable for street running in residential areas.

The wheels, and other moving parts of the machinery, were usually enclosed for safety reasons and to make the engines quieter.

Measures were often taken to prevent the engines from emitting visible smoke or steam.

Usually the engines used coke rather than coal as fuel to avoid emitting smoke; condensers or superheating were used to avoid emitting visible steam. A major drawback of this style of tram was the limited space for the engine, so that these trams were usually underpowered. Steam tram engines faded out around the 1890s to 1900s, being replaced by electric trams.

Another motive system for trams was the cable car, which was pulled along a fixed track by a moving steel cable. The power to move the cable was normally provided at a "powerhouse" site a distance away from the actual vehicle. The London and Blackwall Railway, which opened for passengers in east London, England, in 1840 used such a system.^[23]

The first practical cable car line was tested in San Francisco, in 1873. Part of its success is attributed to the development of an effective and reliable cable grip mechanism, to grab and release the moving cable without damage. The second city to operate cable trams was Dunedin in New Zealand, from 1881 to 1957.

The most extensive cable system in the US was built in Chicago, having been built in stages between 1859 and 1892. New York City developed multiple cable car lines, that operated from 1883 to 1909.^[24] Los Angeles also had several cable car lines, including the Second Street Cable Railroad, which operated from 1885 to 1889, and the Temple Street Cable Railway, which operated from 1886 to 1898.

From 1885 to 1940, the city of Melbourne, Victoria, Australia operated one of the largest cable systems in the world, at its peak running 592 trams on 75 kilometres (47 mi) of track. There were also two isolated cable lines in Sydney, New South Wales, Australia; the North Sydney line from 1886 to 1900,^[25] and the King Street line from 1892 to 1905.

In Dresden, Germany, in 1901 an elevated suspended cable car following the Eugen Langen one-railed floating tram system started operating. Cable cars operated on Highgate Hill in North London and Kennington to Brixton Hill In South London. They also worked around "Upper Douglas" in the Isle of Man from 1897 to 1929 (cable car 72/73 is the sole survivor of the fleet).

Cable cars suffered from high infrastructure costs, since an expensive system of cables, pulleys, stationary engines and lengthy underground vault structures beneath the rails had to be provided. They also required physical strength and skill to operate, and alert operators to avoid obstructions and other cable cars. The cable had to be disconnected ("dropped") at designated locations to allow the cars to coast by inertia, for example when crossing another cable line. The cable would then have to be "picked up" to resume progress, the whole operation requiring precise timing to avoid damage to the cable and the grip mechanism. Breaks and frays in the cable, which occurred frequently, required the complete cessation of services over a cable route while the cable was repaired. Due to overall wear, the entire length of cable (typically several kilometres) would have to be replaced on a regular schedule. After the development of reliable electrically powered trams, the costly high-maintenance cable car systems were rapidly replaced in most locations.

Cable cars remained especially effective in hilly cities, since their nondriven wheels would not lose traction as they climbed or descended a steep hill. The moving cable would physically pull the car up the hill at a steady pace, unlike a low-powered steam or horse-drawn car. Cable cars do have wheel brakes and track brakes, but the cable also helps restrain the car to going downhill at a constant speed. Performance in steep terrain partially explains the survival of cable cars in San Francisco.

The San Francisco cable cars, though significantly reduced in number, continue to perform a regular transportation function, in addition to being a well-known tourist attraction. A single cable line also survives in Wellington, New Zealand (rebuilt in 1979 as a funicular but still called the "Wellington Cable Car"). Another system, actually two separate cable lines with a shared power station in the middle, operates from the Welsh town of Llandudno up to the top of the Great Orme hill in North Wales, UK.

In the late 19th and early 20th centuries a number of systems in various parts of the world employed trams powered by gas, naphtha gas or coal gas in particular. Gas trams are known to have operated between Alphington and Clifton Hill in the northern suburbs of Melbourne, Australia (1886–1888); in Berlin and Dresden, Germany; in Estonia (1921–1951); between Jelenia Góra, Cieplice, and Sobieszów in Poland (from 1897); and in the UK at Lytham St Annes, Neath (1896–1920), and Trafford Park, Manchester (1897–1908).

On 29 December 1886 the Melbourne newspaper The Argus reprinted a report from the San Francisco Bulletin that Mr Noble had demonstrated a new 'motor car' for tramways 'with success'. The tramcar 'exactly similar in size, shape, and capacity to a cable grip car' had the 'motive power' of gas 'with which the reservoir is to be charged once a day at power stations by means of a rubber hose'. The car also carried an electricity generator for 'lighting up the tram and also for driving the engine on steep grades and effecting a start'.^[26]

Comparatively little has been published about gas trams.

However, research on the subject was carried out for an article in the October 2011 edition of "The Times", the historical journal of the Australian Association of Timetable Collectors, now the Australian Timetable Association.^{[27][28][29][30]}

A tram system powered by compressed natural gas was due to open in Malaysia in 2012,^[31] but the news about the project appears to have dried up.

The world's first electric tram line operated in Sestroretsk near Saint Petersburg, Russia, invented and tested by Fyodor Pirotsky in 1880.^[32][33] The second line was the Gross-Lichterfelde tramway in Lichterfelde near Berlin in Germany, which opened in 1881. It was built by Werner von Siemens who contacted Pirotsky. This was world's first commercially successful electric tram. It initially drew current from the rails, with overhead wire being installed in 1883.^[34]

In Britain, Volk's electric railway was opened in 1883 in Brighton (see Volk's Electric Railway). This two kilometer line, re-gauged to 2 ft 9 in (838 mm) in 1884, remains in service to this day, and is the oldest operating electric tramway in the world. Also in 1883, Mödling and Hinterbrühl Tram was opened near Vienna in Austria. It was the first tram in the world in regular service that was run with electricity served by an overhead line with pantograph current collectors. The Blackpool Tramway, was opened in Blackpool, UK on 29 September 1885 using conduit collection along Blackpool Promenade. This system is still in operation in a modernised form.^[35]

Earliest tram system in Canada was by John Joseph Wright, brother of the famous mining entrepreneur Whitaker Wright, in Toronto in 1883. In the US, multiple functioning experimental electric trams were exhibited at the 1884 World Cotton Centennial World's Fair in New Orleans, Louisiana, but they were not deemed good enough to replace the Lamm fireless engines then propelling the St. Charles Avenue Streetcar in that city. The first commercial installation of an electric streetcar in the United States was built in 1884 in Cleveland, Ohio and operated for a period of one year by the East Cleveland Street Railway Company.^[36] Trams were operated in Richmond, Virginia, in 1888, on the Richmond Union Passenger Railway built by Frank J. Sprague. Sprague later developed multiple unit control, first demonstrated in Chicago in 1897, allowing multiple cars to be coupled together and operated by a single motorman. This gave rise to the modern subway train. Following the improvement of an overhead "trolley" system on streetcars for collecting electricity from overhead wires by Sprague, electric tram systems were rapidly adopted across the world.

Earlier installations proved difficult or unreliable.

Siemens' line, for example, provided power through a live rail and a return rail, like a model train, limiting the voltage that could be used, and delivering electric shocks to people and animals crossing the tracks.^[37] Siemens later designed his own version of overhead current collection, called the bow collector, and Thorold, Ontario, opened in 1887, and was considered quite successful at the time. While this line proved quite versatile as one of the earliest fully functional electric streetcar installations, it required horse-drawn support while climbing the Niagara Escarpment and for two months of the winter when hydroelectricity was not available. It continued in service in its original form into the 1950s.

Sidney Howe Short designed and produced the first electric motor that operated a streetcar without gears. The motor had its armature direct-connected to the streetcar's axle for the driving force.^{[38][39][40][41][42]} Short pioneered "use of a conduit system of concealed feed" thereby eliminating the necessity of overhead wire and a trolley pole for street cars and railways.^[43][38][39] While at the University of Denver he conducted important experiments which established that multiple unit powered cars were a better way to operate trains and trolleys.^[38][39]

Sarajevo built a citywide system of electric trams in 1895.^[44] Budapest established its tramway system in 1887, and its ring line has grown to be the busiest tram line in Europe, with a tram running every 60 seconds at rush hour. Bucharest and Belgrade^[45] ran a regular service from 1894.^[46][47] Ljubljana introduced its tram system in 1901 – it closed in 1958.^[48] Oslo had the first tramway in Scandinavia, starting operation on 2 March 1894.^[49]

The first electric tramway in Australia was a Sprague system demonstrated at the 1888 Melbourne Centennial Exhibition in Melbourne; afterwards, this was installed as a commercial venture operating between the outer Melbourne suburb of Box Hill and the then tourist-oriented country town Doncaster from 1889 to 1896.^[50] As well, electric systems were built in Adelaide, Ballarat, Bendigo, Brisbane, Fremantle, Geelong, Hobart, Kalgoorlie, Launceston, Leonora, Newcastle, Perth, and Sydney.

By the 1970s, the only full tramway system remaining in Australia was the Melbourne tram system.

However, there were also a few single lines remaining elsewhere: the Glenelg Tram, connecting Adelaide to the beachside suburb of Glenelg, and tourist trams in the Victorian Goldfields cities of Bendigo and Ballarat. In recent years the Melbourne system, generally recognised as one of the largest in the world, has been considerably modernised and expanded. The Adelaide line has also been extended to the Entertainment Centre, and work is progressing on further extensions.^[51] Sydney re-introduced trams (or light rail) on 31 August 1997. A completely new system, known as G:link, was introduced on the Gold Coast, Queensland on 20 July 2014. The Newcastle Light Rail opened in February 2019, while the Canberra light rail is scheduled to open in April 2019.^[52] This will be the first time that there have been trams in Canberra, even though Walter Burley Griffin's 1914-1920 plans for the capital then in the planning stage did propose a Canberra tram system.^[53]

In Japan, the Kyoto Electric railroad was the first tram system, starting operation in 1895.^[54] By 1932, the network had grown to 82 railway companies in 65 cities, with a total network length of 1,479 km (919 mi).^[55] By the 1960s the tram had generally died out in Japan.

Two rare but significant alternatives were conduit current collection, which was widely used in London, Washington, D.C. and New York City, and the surface contact collection method, used in Wolverhampton (the Lorain system), Torquay and Hastings in the UK (the Dolter stud system), and currently in Bordeaux, France (the ground-level power supply system).

The convenience and economy of electricity resulted in its rapid adoption once the technical problems of production and transmission of electricity were solved.

Electric trams largely replaced animal power and other forms of motive power including cable and steam, in the late 19th and early 20th centuries.

There is one particular hazard associated with trams powered from a trolley pole off an overhead line.

Since the tram relies on contact with the rails for the current return path, a problem arises if the tram is derailed or (more usually) if it halts on a section of track that has been particularly heavily sanded by a previous tram, and the tram loses electrical contact with the rails.

In this event, the underframe of the tram, by virtue of a circuit path through ancillary loads (such as interior lighting), is live at the full supply voltage, typically 600 volts.

In British terminology such a tram was said to be ‘grounded’—not to be confused with the US English use of the term, which means the exact opposite.

Any person stepping off the tram completed the earth return circuit and could receive a nasty electric shock.

In such an event the driver was required to jump off the tram (avoiding simultaneous contact with the tram and the ground) and pull down the trolley pole before allowing passengers off the tram.

Unless derailed, the tram could usually be recovered by running water down the running rails from a point higher than the tram, the water providing a conducting bridge between the tram and the rails.

In the 2000s, two companies introduced catenary-free designs.

Alstom's Citadis line uses a third rail, and Bombardier's PRIMOVE LRV is charged by contactless induction plates embedded in the trackway.^[56]

In some places, other forms of power were used to power the tram.

As early as 1834, Thomas Davenport, a Vermont blacksmith, had invented a battery-powered electric motor which he later patented. The following year he used it to operate a small model electric car on a short section of track four feet in diameter.^[57][58]

Attempts to use batteries as a source of electricity were made from the 1880s and 1890s, with unsuccessful trials conducted in among other places Bendigo and Adelaide in Australia, and for about 14 years as The Hague accutram of HTM in the Netherlands. The first trams in Bendigo, Australia, in 1892, were battery-powered but within as little as three months they were replaced with horse-drawn trams. In New York City some minor lines also used storage batteries. Then, comparatively recently, during the 1950s, a longer battery-operated tramway line ran from Milan to Bergamo. In China there is a Nanjing battery Tram line and has been running since 2014.^[59]

Paris operated trams that were powered by compressed air using the Mekarski system.

The Convict Tramway ^[60] was hauled by human power in the form of convicts from the Port Arthur convict settlement.^[61] and was created to replace the hazardous sea voyage from Hobart to Port Arthur, Tasmania.^[62][60] Charles O'Hara Booth oversaw the construction of the tramway.^[63]

It opened in 1836 and ran for 8 km (5 miles) from Oakwood to Taranna.^[64] By most definitions, the tramway was the first passenger-carrying railway/tramway in Australia.^[62] An unconfirmed report says that it continued to Eaglehawk Neck and, if this was so, the length of the tramway would have been more than doubled. The tramway carried passengers and freight, and ran on wooden rails. The gauge is unknown. The date of closure is unknown, but it was certainly prior to 1877.^[65]

In March 2015, China South Rail Corporation (CSR) demonstrated the world's first hydrogen fuel cell vehicle tramcar at an assembly facility in Qingdao. The chief engineer of the CSR subsidiary CSR Sifang Co Ltd., Liang Jianying, said that the company is studying how to reduce the running costs of the tram.^[66][67]

The Trieste–Opicina tramway in Trieste operates a hybrid funicular tramway system. Conventional electric trams are operated in street running and on reserved track for most of their route. However, on one steep segment of track, they are assisted by cable tractors, which push the trams uphill and act as brakes for the downhill run. For safety, the cable tractors are always deployed on the downhill side of the tram vehicle.

Similar systems were used elsewhere in the past, notably on the Queen Anne Counterbalance in Seattle and the Darling Street wharf line in Sydney.

Hastings and some other tramways, for example Stockholms Spårvägar in Sweden and some lines in Karachi, used petrol trams. Galveston Island Trolley in Texas operated diesel trams due to the city's hurricane-prone location, which would result in frequent damage to an electrical supply system.

Although Portland, Victoria promotes its tourist tram^[68] as being a cable car it actually operates using a hidden diesel motor. The tram, which runs on a circular route around the town of Portland, uses dummies and salons formerly used on the extensive Melbourne cable tramway system and now beautifully restored.

In the mid-20th century many tram systems were disbanded, replaced by buses, automobiles or rapid transit. The General Motors streetcar conspiracy was a case study of the decline of trams in the United States. In the 21st century, trams have been re-introduced in cities where they had been closed down for decades (such as Tramlink in London), or kept in heritage use (such as Spårväg City in Stockholm). Vehicle fabricates from the 1990s and onwards (such as Bombardier's Flexity series and Alstom Citadis) are usually low-floor trams with features such as articulation and regenerative braking.

Articulated trams, invented and first used by the Boston Elevated Railway in 1912–13^[69] at a total length of about twelve meters long (40 ft) for each pioneering example of twin-section articulated tram car, have two or more body sections, connected by flexible joints and a round platform at their pivoting midsection(s). Like articulated buses, they have increased passenger capacity. In practice, these trams can be up to 56 metres (184 ft) long (such as CAF Urbos 3 in Budapest, Hungary),^[70] while a regular tram has to be much shorter. With this type, the articulation is normally suspended between carbody sections.

In the Škoda ForCity, which is the world's first 100% low floor tram with pivoting bogies, a Jacobs bogie supports the articulation between the two or more carbody sections. An articulated tram may be low-floor variety or high (regular) floor variety. Newer model trams may be up to 72 metres (236 ft) long and carry 510 passengers at a comfortable 4 passengers/m2. At crush loadings this would be even higher.^[71]

Since the 19th century goods have been carried on rail vehicles through the streets, often near docks and steelworks, for example the Weymouth Harbour Tramway in Weymouth, Dorset.^[72] Belgian vicinal tramway routes were used to haul agricultural produce, timber and coal from Blégny colliery while several of the US interurbans carried freight. In Australia, three different "Freight Cars" operated in Melbourne between 1927 and 1977^[73] and the city of Kislovodsk in Russia had a freight-only tram system consisting of one line which was used exclusively to deliver bottled Narzan mineral water to the railway station.^[74]

Today, the German city of Dresden has a regular CarGoTram service, run by the world's longest tram trainsets (59.4 metres (195 ft)), carrying car parts across the city centre to its Volkswagen factory.^[75] In addition to Dresden, the cities of Vienna and Zürich currently use trams as mobile recycling depots.

At the turn of the 21st century, a new interest has arisen in using urban tramway systems to transport goods.

The motivation now is to reduce air pollution, traffic congestion and damage to road surfaces in city centres.

One recent proposal to bring cargo tramways back into wider use was the plan by City Cargo Amsterdam to reintroduce them into the city of Amsterdam. In the spring of 2007 the city piloted this cargo tram operation, which among its aims aimed to reduce particulate pollution in the city by 20% by halving the number of lorries (5,000) unloading in the inner city during the permitted timeframe from 07:00 till 10:30. The pilot involved two cargo trams, operating from a distribution centre and delivering to a "hub" where special electric trucks delivered the trams' small containers to their final destination. The trial was successful, releasing an intended investment of €100 million in a fleet of 52 cargo trams distributing from four peripheral "cross docks" to 15 inner-city hubs by 2012. These specially built vehicles would be 30 feet (9.14 m) long with 12 axles and a payload of 30 tonnes (33.1 short tons; 29.5 long tons). On weekdays, trams are planned to make 4 deliveries per hour between 7 a.m. and 11 a.m. and two per hour between 11 a.m. and 11 p.m. With each unloading operation taking on average 10 minutes, this means that each site would be active for 40 minutes out of each hour during the morning rush hour. In early 2009 the scheme was suspended owing to the financial crisis impeding fund-raising.^[76][77]

In 1937, Melbourne passenger tramcar C class number 30 was converted for transporting dogs and their owners to the Royal Melbourne Showgrounds. It was known as the "dog car", and was scrapped in 1955.^[73][78]

A double-decker tram is a tram that has two levels. Some double-decker trams have open tops. The earliest double-deck trams were horse drawn. The first electric double-deck trams were those built for the Blackpool Tramway in 1898, one of which survives at the National Tramway Museum.

Double decker trams were commonplace in Great Britain and Dublin Ireland before most tramways were torn up in the 1950s and 1960s. New York City's New York Railways experimented in 1912 with a Brill double deck Hedley-Doyle stepless centre entrance car, nicknamed the "Broadway Battleship", a term that spread to other large streetcars.^[79] Hobart, Tasmania, Australia made extensive use of double decker trams. Arguably the most unusual double-decker tram used to run between the isolated Western Australian outback town of Leonora and the nearby settlement of Gwalia.

Double decker trams still operate in Alexandria, Blackpool, Hong Kong, Dubai and Oranjestad.

Many early 20th century trams used a lowered central section between the bogies (trucks). This made passenger access easier, reducing the number of steps required to reach the inside of the vehicle. These cars were frequently referred to as "drop-centres". It is believed that the design first originated in Christchurch, New Zealand, in 1906 when Boon & Co Ltd. built 26 such trams in three series.^[80] A number of these trams have been preserved. They were a popular design in Australia and New Zealand, with at least 780 such tramcars being built for use in Melbourne alone. Trams built since the 1970s have had conventional high or low floors.

Specially appointed hearse trams, or funeral trolley cars, were used for funeral processions in many cities in the late 19th and early 20th century, particularly cities with large tram systems. The earliest known example in North America was Mexico City, which was already operating 26 funeral cars in 1886.^[9]*The%20Time%20of%20the%20Tro]]*The%20Time%20of%20the%20Tro]]*n the United States, funeral cars were often given names. At the turn of the century, "almost every major city [in the US] had one or more"

In Milan, Italy, hearse trams were used from the 1880s (initially horse-drawn) to the 1920s.

The main cemeteries, Cimitero Monumentale and Cimitero Maggiore, included funeral tram stations.

Additional funeral stations were located at Piazza Firenze and at Porta Romana.^[82] In the mid-1940s at least one special hearse tram was used in Turin, Italy.

It was introduced due to the wartime shortage of automotive fuel.^[83] Newcastle, Australia also operated two hearse trams^[84] between 1896 and 1948.

From around the 1990s, light rail vehicles not made for the occasional high platform light rail system have usually been of partial or fully low-floor design, with the floor 300 to 360 mm (11.8 to 14.2 in) above top of rail, a capability not found in older vehicles.

This allows them to load passengers, including those in wheelchairs or with perambulators directly from low-rise platforms that are not much more than raised footpaths/sidewalks. This satisfies requirements to provide access to disabled passengers without using expensive wheelchair lifts, while at the same time making boarding faster and easier for other passengers. Passengers appreciate the ease of boarding and alighting from low-floor trams and moving about inside 100 per cent low-floor trams. Passenger satisfaction with low-floor trams is high.^[85] In some jurisdictions this has even been made mandatory since the 1990s, for example by the HMRI in Britain and the Disability discrimination act in the United Kingdom and other Commonwealth countries.

Various companies have developed particular low-floor designs, varying from part-low-floor (with internal steps between the low-floor section and the high-floor sections over the bogies), e.g. Citytram^[86] and Siemens S70, to 100 per cent low-floor, where the floor passes through a corridor between the drive wheels, thus maintaining a relatively constant (stepless) level from end to end of the tram.

Prior to the introduction of the Škoda ForCity, this carried the mechanical penalty of requiring bogies to be fixed and unable to pivot (except for less than 5 degrees in some trams) and thus reducing curve negotiation. This creates undue wear on the tracks and wheels.

Low-floor trams are now running in many cities around the world, including Adelaide, Amsterdam, Bratislava, Dublin, Gold Coast, Helsinki, Hiroshima, Houston, Istanbul, Melbourne, Milan, Prague, Sydney, Lviv and many others.

The Ultra Low Floor or (ULF) tram is a type of low-floor tram operating in Vienna, Austria as of 1997 and in Oradea, Romania, with the lowest floor-height of any such vehicle. In contrast to other low-floor trams, the floor in the interior of ULF is at sidewalk height (about 18 cm or 7 inches above the road surface), which makes access to trams easy for passengers in wheelchairs or with baby carriages. This configuration required a new undercarriage. The axles had to be replaced by a complicated electronic steering of the traction motors. Auxiliary devices are installed largely under the car's roof.

Most low-floor trams carry the mechanical penalty of requiring bogies to be fixed and unable to pivot.^[87] This creates undue wear on the tracks and wheels and reduces the speed at which a tram can drive through a curve.^[88] Some manufacturers such as Citadis deal with the issue by introducing partially high floor trams. Others, such as Škoda, developed pivoting bogies at the ends and with jacobs bogies between the articulations for the Škoda 15 T, but this solution proved expensive.

Most systems had cars that were converted to specific uses on the system, other than simply the carriage of passengers.

As just one example of a system, Melbourne used or uses the following "technical" cars: a ballast motor, ballast trailers, blow-down cars, breakdown cars, conductors' or drivers' instruction cars, a laboratory testing car, a line marking car, a pantograph testing car, per way locomotives, a rail hardener locomotive, a scrapper car, scrubbers, sleeper carriers, track cleaners, a welding car, and a wheel transport car. Some were built new for specific purposes, including: rail grinders, scrubbers/track cleaners, and a workshops locomotive.^[73][78]

Munich tram No.24, delivered in 1912, was refurbished as a mobile library in 1928.

Known as "Städtische Wanderbücherei München", it was in public service until 1970.

It was preserved and is now on public display in a railway museum in Hanover.^[89] Edmonton, Alberta, used a streetcar bookmobile from 1941 to 1956.

After World War II, in both Warsaw and Wrocław, Poland, so-called trams-nurseries^[90] were in operation, collecting children from the workplaces of their parents (often tram employees). These mobile nurseries either carried the children around the system or delivered them to the nursery school run by transport company.^[91]

A number of systems have introduced restaurant trams, particularly as a tourist attraction.

This is specifically a modern trend.

Systems which have or have had restaurant trams include Adelaide, Bendigo and Melbourne, in Australia; Brussels in Belgium; The Hague in the Netherlands; Christchurch in New Zealand;^[92] Milan, Rome and Turin in Italy; Moscow, Russia; Almaty, Kazakhstan ^[93][94] and Zürich, Switzerland.

Restaurant trams are particularly popular in Melbourne where three of the iconic W class trams have been converted. All three often run in tandem and there are usually multiple meal sittings. Bookings often close months in advance. As from mid-October 2018, Melbourne's restaurant trams were temporarily taken off the road after failing a Yarra Trams' safety assessment due to badly weathered underlying structures. Until the trams again meet safety standards, the trams are offering stationary dining.^[95]

Bistro trams with buffets operated on ordinary services between 1924 and 2014 on the U76 Rheinbahn route between Krefeld and Düsseldorf in Germany,^[96] and for a short period in 1911 on the Amsterdam-Zandvoort line.

Helsinki in Finland has a pub tram. Frankfurt, Germany, has a tourist circle line called "Ebbelwei-Express", in which the traditional local drink "Apfelwein" (locally called "Ebbelwei", a type of hard cider) is served.^[97]

A double-ended tram has an operator's cab and controls at each end of the vehicle, which allows it to easily be driven at full speed in either direction on a continuous segment of track.

Typically at the end of a run, the tram's operator will walk from one end of the tram to the other, and then commence the tram route in the other direction.

The tram is usually switched to another track by use of crossover points or Y-points.

Conversely, a single-ended vehicle needs a method of turning at termini so that the operator's cab is in the front of the tram for the reverse journey.

This usually necessitates a turning loop or triangle.

On the other hand, the single cab and controls and fewer door spaces make the tram lighter, increases passenger accommodation (including many more seats) and effects reductions in equipment, weight, first-cost, maintenance cost, and operating expense.

A single-ended tram has operator's controls at only one end, and can safely be driven at speed in the forward direction but is also capable of reverse movement, typically at slower speed, using a small set of controls at the rear.

The configuration of the doors is usually asymmetrical, favouring the side expected to be closest to the street kerb and footpath. At the end of a run, the tram must be turned around via a balloon loop or some other method, to face in the opposite direction for a return trip.

In addition, if overhead electrical power is fed from a trolley pole, the direction of the trolley pole must be reversed at the end of the run, to ensure that the pole is "pulled" behind or "trailing" the vehicle, to avoid 'dewiring'. This was achieved by a member of the crew swinging the pole through 180 degrees (if there was only one pole) or lowering one pole and raising the other if there were two. More commonly nowadays, a bidirectional pantograph may be used to feed power, eliminating the need for an extra procedure when reversing direction.

Two single-ended trams with doors on both sides may be coupled into a (semi-)permanently coupled married pair or twinset, with operator's controls at each end of the combination. Such a setup is operated as if it were a double-ended tram, except that the operator must exit one vehicle and enter the other, when reversing at the end of the run.

Many systems have retained historical trams which will often run over parts of the system for tourists and tram enthusiasts.

In Melbourne, Australia, a number of the iconic W class run throughout each day in a set route which circles the Central Business District. They are primarily for the use of tourists, although often also used by regular commuters.

A tram-train is a light-rail public transport system where trams run through from an urban tramway network to main-line railway lines which are shared with conventional trains. This allows passengers to travel from suburban areas into city-centre destinations without having to change from a train to a tram.

Tram-train operation uses vehicles such as the Flexity Link and Regio-Alstom Citadis, which are suited for use on urban tram lines and also meet the necessary indication, power, and strength requirements for operation on main-line railways.

It has been primarily developed in Germanic countries, in particular Germany and Switzerland.

Karlsruhe is a notable pioneer of the tram-train.

Two former passenger cars from the Melbourne system were converted and used as mobile offices within the Preston Workshops between 1969 and 1974, by personnel from Commonwealth Engineering and ASEA who were connected with the construction of Melbourne's Z Class cars.^[73]

A rubber-tyred tram is a guided bus which is guided by a fixed rail on the ground and uses overhead cables like a conventional tram. This can allow the vehicles to match the capacity of conventional trams and cope with gradients up to 13% due to the rubber tyres. There are two systems which use this technology: the Guided Light Transit (GLT) and Translohr. The GLT "trams" are legally considered buses as they have steering wheels and can leave the fixed rail when requirements dictate e.g. when journeying to a depot while a Translohr "tram" cannot operate without a guidance rail and are generally not considered buses.^[98]

With the development of technologies for self-guided vehicles, it is now possible to dispense with the guide rail.

The Autonomous Rail Rapid Transit system planned for Zouzhou in China follows a virtual track.

The Eurotram series was developed by Socimi of Italy. It is used by Strasbourg, Milan, and Porto. The Eurotram has a modern design that makes it look almost as much like a train as a tram, and has large windows along its entire length.^[99]

The Citadis tram, flagship of the French manufacturer Alstom, enjoys an innovative design combining lighter bogies with a modular concept for carriages providing more choices in the types of windows and the number of cars and doors.^[100] The recent Citadis-Dualis, intended to run at up to 100 km/h (62 mph), is suitable for stop spacings ranging from 500 m (1,600 ft) to 5 km (3.1 mi). Dualis is a strictly modular partial low-floor car, with all doors in the low-floor sections.^[101]

There are two main types of tramways, the classic tramway built in the early 20th century with the tram system operating in mixed traffic, and the later type which is most often associated with the tram system having its own right of way.

Tram systems that have their own right of way are often called light rail but this does not always hold true. Though these two systems differ in their operation, their equipment is much the same.

Trams were traditionally operated with separate levers for applying power and brakes.

More modern vehicles use a locomotive-style controller which incorporate a dead man's switch. The success of the PCC streetcar had also seen trams use automobile-style foot controls allowing hands-free operation, particularly when the driver was responsible for fare collection.

Electric trams use various devices to collect power from overhead lines. The most common device found today is the pantograph, while some older systems use trolley poles or bow collectors. Ground-level power supply has become a recent innovation. Another new technology uses supercapacitors; when an insulator at a track switch cuts off power from the tram for a short distance along the line, the tram can use energy stored in a large capacitor to drive the tram past the gap in the power feed.^[102] A rather obsolete system for power supply is conduit current collection.

The old tram systems in London, Manhattan (New York City), and Washington, D.C., used live rails, like those on third-rail electrified railways, but in a conduit underneath the road, from which they drew power through a plough. It was called Conduit current collection. Washington's was the last of these to close, in 1962. Today, no commercial tramway uses this system. More recently, a modern equivalent to these systems has been developed which allows for the safe installation of a third rail on city streets, which is known as surface current collection or ground-level power supply; the main example of this is the new tramway in Bordeaux.

A ground-level power supply system also known as Surface current collection or Alimentation par le sol (APS) is an updated version of the original stud type system.

APS uses a third rail placed between the running rails, divided electrically into eight-metre powered segments with three metre neutral sections between.

Each tram has two power collection skates, next to which are antennas that send radio signals to energize the power rail segments as the tram passes over them.

Older systems required mechanical switching systems which were susceptible to environmental problems.

At any one time no more than two consecutive segments under the tram should actually be live.

Wireless and solid state switching remove the mechanical problem.

Alstom developed the system primarily to avoid intrusive power supply cables in the sensitive area of the old city of old Bordeaux.^[103]

Route patterns vary greatly among the world's tram systems, leading to different network topologies.

The resulting route patterns are very different.

Some have a rational structure, covering their catchment area as efficiently as possible, with new suburbs being planned with tramlines integral to their layout – such is the case in Amsterdam. Bordeaux and Montpellier have built comprehensive networks, based on radial routes with numerous interconnections, within the last two decades. Some systems serve only parts of their cities, with Berlin being the prime example, owing to the fact that trams survived the city's political division only in the Eastern part. Other systems have ended up with a rather random route map, for instance when some previous operating companies have ceased operation (as with the tramways vicinaux/buurtspoorwegen in Brussels) or where isolated outlying lines have been preserved (as on the eastern fringe of Berlin). In Rome, the remnant of the system comprises 3 isolated radial routes, not connecting in the ancient city centre, but linked by a ring route. Some apparently anomalous lines continue in operation where a new line would not on rational grounds be built, because it is much more costly to build a new line than continue operating an existing one.

In some places, the opportunity is taken when roads are being repaved to lay tramlines (though without erecting overhead cables) even though no service is immediately planned: such is the case in Leipzigerstraße in Berlin, the Haarlemmer Houttuinen in Amsterdam, and Botermarkt in Ghent.

Tram systems operate across national borders in Basel (from Switzerland into France and Germany) and Strasbourg (From France into Germany). It is planned to open a line linking Hasselt (Belgium) with Maastricht (Netherlands) in 2021.

Tramway track can have different rail profiles to accommodate the various operating environments of the vehicle. They may be embedded into concrete for street-running operation, or use standard ballasted track with railroad ties on high-speed sections. A more ecological solution is to embed tracks into grass turf.

Tramway tracks use a grooved rail with a groove designed for tramway or railway track in pavement or grassed surfaces (grassed track or track in a lawn). The rail has the railhead on one side and the guard on the other. The guard provides accommodation for the flange. The guard carries no weight, but may act as a checkrail. Grooved rail was invented in 1852 by Alphonse Loubat, a French inventor who developed improvements in tram and rail equipment, and helped develop tram lines in New York City and Paris. The invention of grooved rail enabled tramways to be laid without causing a nuisance to other road users, except unsuspecting cyclists, who could get their wheels caught in the groove. The grooves may become filled with gravel and dirt (particularly if infrequently used or after a period of idleness) and need clearing from time to time, this being done by a "scrubber" tram. Failure to clear the grooves can lead to a bumpy ride for the passengers, damage to either wheel or rail and possibly derailing.

In narrow situations double-track tram lines sometimes reduce to single track, or, to avoid switches, have the tracks interlaced, e.g. in the Leidsestraat in Amsterdam on three short stretches (see map detail ^[236] ); this is known as interlaced or gauntlet track. There is a UK example of interlaced track on the Tramlink, just west of Mitcham Station, where the formation is narrowed by an old landslip causing an obstruction. (See photo in Tramlink entry).

Historically, the track gauge has had considerable variations, with narrow gauge common in many early systems. However, most light rail systems are now standard gauge. An important advantage of standard gauge is that standard railway maintenance equipment can be used on it, rather than custom-built machinery. Using standard gauge also allows light rail vehicles to be delivered and relocated conveniently using freight railways and locomotives.

Another factor favoring standard gauge is that low-floor vehicles are becoming popular, and there is generally insufficient space for wheelchairs to move between the wheels in a narrow gauge layout.

Standard gauge also enables – at least in theory – a larger choice of manufacturers and thus lower procurement costs for new vehicles.

However, other factors such as electrification or loading gauge for which there is more variation may require costly custom built units regardless.

Tram stops may be similar to bus stops in design and use, particularly in street-running sections, where in some cases other vehicles are legally required to stop clear of the tram doors. Some stops may resemble to railway platforms, particularly in private right-of-way sections and where trams are boarded at standard railway platform height, as opposed to using steps at the doorway or low-floor trams.

Approximately 5,000 new trams are manufactured each year.

As of February 2017, 4,478 new trams were on order from their makers, with options being open for a further 1,092.^[104]

The main manufacturers are:

Trams are in a period of growth, with about 800 tram systems operating around the world, 10 or so new systems being opened each year, and many being gradually extended.^[114] Some of these systems date from the late 19th or early 20th centuries. In the past 20 years their numbers have been augmented by modern tramway or light rail systems in cities that had discarded this form of transport. There have also been some new tram systems in cities that never previously had them.

Tramways with tramcars (British English) or street railways with streetcars (North American English) were common throughout the industrialised world in the late 19th and early 20th centuries but they had disappeared from most British, Canadian, French and US cities by the mid-20th century.^[115]

By contrast, trams in parts of continental Europe continued to be used by many cities, although there were contractions in some countries, including the Netherlands.^[116]

Since 1980 trams have returned to favour in many places, partly because their tendency to dominate the roadway, formerly seen as a disadvantage, is now considered to be a merit since it raises the visibility of public transport (encouraging car users to change their mode of travel), and enables streets to be reconfigured to give more space to pedestrians, making cites more pleasant places to live.

New systems have been built in the United States, Great Britain, Ireland, Italy, France, Australia and many other countries.

In Milan, Italy, the old "Ventotto" trams are considered by its inhabitants a "symbol" of the city. The same can be said of trams in Melbourne in general, but particularly the iconic W class. The Toronto streetcar system had similarly become an iconic symbol of the city, operating the largest network in the Americas as well as the only large-scale tram system in Canada (not including light rail systems, or heritage lines).^[117][118]

The largest tram ((classic tram, streetcar, straßenbahn) and fast tram (light rail, stadtbahn)) networks in the world by route length (as of 2016)^[119] are Melbourne (256 km; 159 mi),^[120] Saint Petersburg (205.5 km; 127.7 mi),^[121] Cologne (194.8 km; 121.0 mi),^[122] Berlin (191.6 km; 119.1 mi),^[123] Moscow (183 km; 114 mi),^[124] Milan (181.8 km; 113.0 mi),^[125] Budapest (172 km; 107 mi),^[126] Katowice agglomeration (171 km; 106 mi)^[127] and Vienna (170 km; 110 mi).^[128]

Other large systems include (but are not limited to): Dallas Light Rail,^[129] modern streetcar^[130] and heritage streetcar^[131] (155 km; 96 mi), Sofia (153.6 km; 95.4 mi),^[119] Leipzig (148.3 km; 92.1 mi),^[132] Łódź (145 km; 90 mi),^[133] Bucharest (143 km; 89 mi),^[134] Prague (142.4 km; 88.5 mi),^[135] Kiev (139.9 km; 86.9 mi), Brussels (138.9 km; 86.3 mi), Warsaw (138 km; 86 mi), Dresden (134 km; 83 mi), Los Angeles (133.1 km; 82.7 mi),^[136] Bonn Stadtbahn and streetcars (125.32 km; 77.87 mi), Stuttgart (124.5 km; 77.4 mi),^[137] Hanover (121 km; 75 mi), Zagreb (116.3 km; 72.3 mi), Bremen (114.6 km; 71.2 mi), Portland metropolitan area light rail and streetcars (108.2 km; 67.2 mi), Paris (104.9 km; 65.2 mi),^[138] Mannheim/Ludwigshafen (103.4 km; 64.2 mi),^[139][140] Riga (99.52 km; 61.84 mi), Gothenburg (95 km; 59 mi), Kassel (93.3 km; 58.0 mi), Manchester (92.5 km; 57.5 mi), Kraków (90 km; 56 mi),^[141] Dnipro (87.8 km; 54.6 mi), Halle (Saale) (87.6 km; 54.4 mi), San Diego (86.1 km; 53.5 mi), Pavlodar (86 km; 53 mi),^[142] Turin (84 km; 52 mi), Bochum/Gelsenkirchen (84 km; 52 mi), Zurich (84 km; 52 mi),^[143] Toronto (83 km; 52 mi),^[144] Amsterdam (80.5 km; 50.0 mi),^[145] Munich (79 km; 49 mi),^[146] Antwerp (79 km; n49 mi),^[147] Denver (76 km; 47 mi), Iași (76 km; 47 mi), Salt Lake Valley light rail and streetcar (75.42 km (46.86 mi)), Dortmund (75 km; 47 mi), Rotterdam (75 km; 47 mi),^[148] St. Louis Metropolitan Area (74 km; 46 mi), Lviv (73.5 km; 45.7 mi), Mykolaiv (72.83 km; 45.25 mi), Karlsruhe (71.5 km; 44.4 mi), Brno (70.4 km; 43.7 mi), Porto (70 km; 43 mi), Sacramento (69 km; 43 mi),^[149] Frankfurt am Main (68 km; 42 mi), San Jose and its suburbs (67.9 km; 42.2 mi), Lyon (66.3 km; 41.2 mi),^[150] Ostrava (65.7 km; 40.8 mi), Basel (65.7 km; 40.8 mi, Donetsk (65.7 km; 40.8 mi), Poznań (65.6 km; 40.8 mi), Minsk (62.8 km; 39.0 mi), Szczecin (60 km; 37 mi), Graz (59.8 km; 37.2 mi), Montpellier (55.6 km; 34.5 mi),^[151][152] Pyongyang (53.5 km; 33.2 mi), Essen (52.4 km; 32.6 mi) and Gdańsk (52.2 km; 32.4 mi). This list is not exhaustive.

The length of the following networks is disputed: Philadelphia trolleycar network comprise from Subway–Surface Trolley Lines with line length 31.9 km; 19.8 mi^[153] or by another source 100.8 km; 62.6 mi (the sum of all lines (lines 10 (18.7 km; 11.6 mi), 11 (21.4 km; 13.3 mi), 13 (18.3 km; 11.4 mi), 34 (16.3 km; 10.1 mi) and 36 (26.1 km; 16.2 mi)), light rail routes 101 and 102 with length 19.2 km (11.9 mi)^[153] and heritage route 15 (line length 13.7 km (8.5 mi)).^[153] Put together, it measures 64.6 or 133.5 km (40.1 or 83.0 mi) of line length. The route length is 86.6 km (53.8 mi).^[153] Next, San Francisco light rail and streetcars have route length 50 km (31 mi)^[154] or 59.4 km (36.9 mi).^[153] Except it, in city is 8.3 km (5.2 mi)^[154] of cable car. Next networks with disputed route length are Düsseldorf Stadtbahn (76 km; 47 mi)^[156] or 78 km (48 mi)^[157]/streetcars 72 km (45 mi)^[156] or 68.5 km (42.6 mi),^[157] The Hague (105 km; 65 mi)^[158] or by other sources 142 km (88 mi),^[159] Strasbourg (40.4 km; 25.1 mi)^[160] or 57.5 km (35.7 mi),^[161] Kolkata (57 km; 35 mi)^[162] or 68 km (42 mi),^[163] Nizhny Novgorod (formerly Gorky) (98 km; 61 mi) or 76.5 km (47.5 mi). This list is not exhaustive.

The longest single tram line in the world is the 68 km (42 mi) Belgian Coast Tram, which runs almost the entire length of the Belgian coast. Another fairly long line is the Valley Metro Rail in Phoenix, Arizona, with its 42 km (26 mi).^[164][165]

Historically, the Paris Tram System was, at its peak, the world's largest system, with 1,111 km (690 mi) of track in 1925 (according to other sources, ca. 640 km (400 mi) of route length in 1930). However it was completely closed in 1938.^[166] The next largest system appears to have been 857 km (533 mi), in Buenos Aires before 19 February 1963. The third largest was Chicago, with over 850 km (530 mi) of track,^[167] but it was all converted to trolleybus and bus services by 21 June 1958. Before its decline, the BVG in Berlin operated a very large network with 634 km (394 mi) of route. Before its system started to be converted to trolleybus (and later bus) services in the 1930s (last tramway closed 6 July 1952), the first-generation London network had 555 km (345 mi) of route in 1931.^[168] In 1958 trams in Rio de Jainero were employed on (433 km; 269 mi) of track. The final line, the Santa teresa route was closed in 1968.^[169] During a period in the 1980s, the world's largest tram system was in Leningrad (now known as St. Petersburg) with 350 km (220 mi), USSR, and was included as such in the Guinness World Records; however Saint Petersburg's tram system has declined in size since the fall of the Soviet Union. Vienna in 1960 had 340 km (211 mi), before the expansion of bus services and the opening of a subway (1976). Substituting subway services for tram routes continues. 320 km (199 mi) was in Minneapolis-Saint Paul in 1947: There streetcars ended 31 October 1953 in Minneapolis and 19 June 1954 in St. Paul.^[170] The Sydney tram network, before it was closed on 25 February 1961, had 291 km (181 mi) of route, and was thus the largest in Australia. As from 1961, the Melbourne system (currently recognised as the world's largest) took over Sydney's title as the largest network in Australia.

Tramway systems were well established in the Asian region at the start of the 20th century, but started a steady decline during the mid to late 1930s.

The 1960s marked the end of its dominance in public transportation with most major systems closed and the equipment and rails sold for scrap; however, some extensive original lines still remain in service in Hong Kong and Japan.

In recent years there has been renewed interest in the tram with modern systems being built in Japan and China.

Several cities in China had tram systems during the 20th century; however, by the end of the century, only Dalian, Hong Kong and Changchun remained extant.

However the 21st century has seen a resurgence in development of tram transport as China struggles with urban traffic congestion and pollution with at least 15 systems operating.

Hong Kong has an exclusive fleet of double-decker trams.

As of 2017, Chengdu, Sanya, Wuyishan and Haikou have new tram systems under construction. Zhuhai tram line 1 opened in 2017.^[174]

The first Japanese tram line was inaugurated in 1895 as the Kyoto Electric Railroad. The tram reached its zenith in 1932 when 82 rail companies operated 1,479 kilometers of track in 65 cities. The tram declined in popularity through the remaining years of the 1930s and during the 1960s many of the remaining operational tramways were shut down or converted into commuter railway lines.

In India, trams are in operation in Kolkata. Trams were discontinued in Chennai in 1954 and in Mumbai in 1960.^[175]

The Northern and Central areas of the City of Colombo in Sri Lanka had an electric Tram Car system (3 ft 6 in or 1,067 mm gauge). This system commenced operations about 1900 and was discontinued by 1960. However, a new tram system is in the process of being brought to Colombo as part of the plan of Western Region Megapolis.

Other countries with discontinued tram systems include Indonesia, Singapore, Malaysia, Thailand, Pakistan and Vietnam.

However, a tram system is planned for construction in Gwadar, Pakistan where construction started in late 2011. Trams are also under construction in DHA City, Karachi. In China the cities of Beijing, Zhuhai, Nanjing and Shenzhen are planning tram networks for the future.

In many European cities much tramway infrastructure was lost in the mid-20th century, though not always on the same scale as in other parts of the world such as North America.

Most of Central and Eastern Europe retained the majority of its tramway systems and it is here that the largest and busiest tram systems in the world are found.

Whereas most systems and vehicles in the tram sector are found in Central and Eastern Europe, in the 1960s and 1970s, tram systems were shut down in many places in Western Europe, however urban transportation has been experiencing a sustained long running revival since the 1990s.

Many European cities are rehabilitating, upgrading, expanding and reconstructing their old tramway lines and building new tramway lines.^[176]

In North America, these vehicles are called "streetcars" (or "trolleys"); the term tram is more likely to be understood as an aerial tramway or a people-mover. Streetcar systems were developed in late 19th to early 20th centuries in a number of cities throughout North America. However, most North American cities saw its streetcar lines removed in the mid-20th century for a variety of financial, technological and social reasons. Exceptions included Boston,^[177] Cleveland, Mexico City, New Orleans, Newark, Philadelphia, Pittsburgh, San Francisco, and Toronto.

Toronto currently operates the largest streetcar system in the Americas in terms of track length and ridership. Operated by the Toronto Transit Commission, the streetcar system is the only large-scale streetcar system existing in Canada, excluding heritage streetcar, or light rail systems that are operated in other Canadian municipalities. The streetcar system was established in 1861, and used a variety of vehicles in its history, including horse-drawn streetcars, Peter Witt streetcars, and the PCC streetcar. The system currently uses Canadian Light Rail Vehicles, Articulated Light Rail Vehicles, and the Flexity Outlook.^{[178][118][180][181]}

Streetcars once existed in the Canadian cities of Calgary, Edmonton, Halifax, Hamilton, Kingston, Kitchener, London, Montreal, Ottawa, Peterborough, Quebec City, Regina, Saskatoon, Windsor, and Vancouver. However, Canadian cities excluding Toronto, removed their streetcar systems in the mid-20th century. In the late 1970s and early 1980s, light rail systems were introduced in Calgary and Edmonton; with another light rail system established in Ottawa in 2001. In the late 20th century, several Canadian locales restored portions of their defunct streetcar lines, operating them as a heritage feature for tourists. Heritage streetcar lines in Canada include the High Level Bridge Streetcar in Edmonton, the Nelson Electric Tramway in Nelson, and the Whitehorse Waterfront Trolley in Whitehorse

Pittsburgh had kept most of its streetcar system serving the city and many suburbs, making it the longest-lasting large-network streetcar system in the United States.

However, most of Pittsburgh's surviving streetcar lines were converted to light rail in the 1980s.

San Francisco's Muni Metro system is the largest surviving streetcar system in the United States, and has even revived previously closed streetcar lines such as the F Market & Wharves heritage streetcar line. In the late 20th century, several cities installed modern light rail systems, in part along the same corridors as their old streetcars systems, the first of these being the San Diego Trolley in San Diego in 1981.

In the 1980s, some cities in the United States brought back streetcars lines, including Memphis, Tampa, and Little Rock; However, these streetcar systems were designed as heritage streetcar lines, and used vintage or replica-vintage vehicles. The first "second-generation streetcar systems" in North America was opened in Portland in 2001.^[182] The "second-generation streetcar system," utilizes modern vehicles – vehicles that feature low-floor streetcars. These newer streetcar systems were built in several American cities in the early 21st century including Atlanta, Charlotte, Cincinnati, Dallas, Detroit, Kansas City, Milwaukee, Oklahoma City, Seattle, Tucson, and Washington, D.C..

Historically, there have been trams in the following Australian cities and towns: Adelaide, Ballarat, Bendigo, Brisbane, Broken Hill, Fremantle, Gawler, Geelong, Hobart, Kalgoorlie, Launceston, Leonora, Maitland, Melbourne, Moonta–Wallaroo, Newcastle, Perth, Rockhampton, Sorrento, Sydney, and Victor Harbor. These ranged from extensive systems to single lines. The Sydney system, which closed in 1961, was the most extensive and the largest passenger carrier of any Australian public transport system then or since, moving over 400 million passengers per annum, at its peak.

Virtually all known types of motive power have been utilised at some stage, in Australia.

Today, trams can be found in Melbourne (by length, the world's largest system), and to a lesser extent, Adelaide; all other major cities having largely dismantled their networks by the 1970s.

Sydney reintroduced tram services in 1997 on a modern light rail network, while Ballarat and Bendigo retained their trams as heritage systems. In 2008 and 2009, Bendigo conducted trials utilising its heritage trams for regular public transport. Portland, Victoria, introduced a tourist tram in 1996 – this uses a former Melbourne cable car dummy and trailer car, but utilising a hidden diesel motor. A completely new public transport system opened on the Gold Coast, Queensland on 20 July 2014, with a major extension completed in December 2017. The new system is known as the G:link and is the first tram/ light rail system in the state of Queensland since Brisbane closed its tram network in 1969.

The 2010s has also seen a significant expansion of Sydney's network, while the construction of light rail in Canberra became the major issue of the 2016 ACT election, with the ruling parties supporting the project and the opposition opposing it. The government was returned^[183] and Stage 1 of the light rail launched in April 2019.^[184] The railway into the centre of Newcastle was truncated to Wickham on 25 December 2014,^[185][186] The railway line was replaced by the Newcastle Light Rail line in February 2019. There are also loose plans for new systems in Hobart, Tasmania, and on the Sunshine Coast, Queensland.

New Zealand's last public transport tramway system, that of Wellington, closed in 1966. Nevertheless, there had been tramways ranging from large, comprehensive systems to single lines, in Auckland, Christchurch, Dunedin, Gisborne, Invercargill, Napier, New Plymouth, Greymouth, Westport, Hokitika, Ross, Brighton, Charleston, Kamiere and Kamara. New Zealand's tram gauges were not standardised; the 15 systems used no less than five gauges, making swapping of rolling stock from system to system difficult.^[187] Christchurch has subsequently reintroduced heritage trams over a new CBD route, but the overhead wiring plus some track was damaged by the earthquake of 2011. In November 2013 a limited circuit was reopened. Auckland has recently introduced heritage trams into the Wynyard area, near the CBD, using former Melbourne trams. on 9 May 2018, two modern tram / Lightrail routes were announced from Wynyard Quarter, via Queen Street to Auckland Airport via Dominion Road and Onehunga in the South and via Queen Street and Great North Road, Point Chevalier and onto the Northwestern Motorway to Westgate to be running in the early 2020s with a possible further extension to Kumeu/Huapai. Preserved Auckland trams from the MOTAT have made cameo appearances during Heritage Weeks. Heritage lines exist at Auckland's MOTAT, the Wellington Tramway Museum at Queen Elizabeth Park on the Kapiti Coast, the Tramways Trust Wanganui and the Tramway Historical Society at Ferrymead in Christchurch, as well as the Christchurch Tramway Limited in the central city. Whangarei Steam and Model Railway Club also run two former Lisbon trams formally from Aspen, Colorado.

Buenos Aires in Argentina once had one of the most extensive tramway networks in the world with over 857 km (533 mi) of track, most of it dismantled during the 1960s in favour of bus transportation. A new line, the PreMetro line E2 system feeding the Line E of the Buenos Aires Subway has been operating since 1987 on the outskirts of Buenos Aires.

In Cuenca, Ecuador, a tram line started operating since March 2019 as the main public transportation system in the city. The L1 of the Cuenca tram is 20.4 km long with 20 stops and uses Alstom Citadis (302) trains.

The Tranvía del Este in Puerto Madero, Buenos Aires, operated from 2007 to 2012, and it's now dismantled.^[188]

Also in the city of Mendoza, in Argentina, a new tramway system is currently on service since 2012, the Metrotranvía of Mendoza, which will have a route of 12.5 km (7.8 mi) and will link five districts of the Greater Mendoza conurbation.^[189]

In Medellín, Colombia, a tram line began operation on 15 October 2015,^[190][191] as a revival of old Ayacucho tram.^[192]

In Santiago, Chile there are plans for a tramway that will connect the comunes of Las Condes, Lo Barnechea y Vitacura. (tranvía de Las Condes)

Model trams are popular in HO scale (1:87) and O scale (1:48 in the US and generally 1:43,5 and 1:45 in Europe and Asia). They are typically powered and will accept plastic figures inside. Common manufacturers are Roco and Lima, with many custom models being made as well. The German firm Hödl^[201] and the Austrian Halling^[202] specialise in 1:87 scale.^[203]

In the US, Bachmann Industries is a mass supplier of HO streetcars and kits. Bowser Manufacturing has produced white metal models for over 50 years.^[204] There are many boutique vendors offering limited run epoxy and wood models. At the high end are highly detailed brass models which are usually imported from Japan or Korea and can cost in excess of $500. Many of these run on 16.5 mm (0.65 in) gauge track, which is correct for the representation of 4 ft 8 1⁄2 in (1,435 mm) (standard gauge) in HO scale as in US and Japan, but incorrect in 4 mm (1:76.2) scale, as it represents 4 ft 8 1⁄2 in (1,435 mm). This scale/gauge hybrid is called OO scale. O scale trams are also very popular among tram modellers because the increased size allows for more detail and easier crafting of overhead wiring. In the US these models are usually purchased in epoxy or wood kits and some as brass models. The Saint Petersburg Tram Company^[205] produces highly detailed polyurethane non-powered O Scale models from around the world which can easily be powered by trucks from vendors like Q-Car.^[206]

In the US, one of the best resources for model tram enthusiasts is the East Penn Traction Club of Philadelphia ^[207] and Trolleyville a website of the Southern California Traction Club.^[208]

It is thought that the first example of a working model tramcar in the UK built by an amateur for fun was in 1929, when Frank E. Wilson created a replica of London County Council Tramways E class car 444 in 1:16 scale, which he demonstrated at an early Model Engineer Exhibition.

Another of his models was London E/1 1800, which was the only tramway exhibit in the Faraday Memorial Exhibition of 1931.

Together with likeminded friends, Frank Wilson went on to found the Tramway & Light Railway Society^[209] in 1938, establishing tramway modelling as a hobby.

There are many references to trams in popular culture, major references include:-