The U.S. Interior Highlands is a mountainous region in the Central United States spanning northern and western Arkansas , southern Missouri , eastern Oklahoma , and extreme southeastern Kansas . The name is designated by the United States Geological Survey to refer to the combined subregions of the Ouachita Mountains and the Ozark Plateaus . The U.S. Interior Highlands is one of few mountainous regions between the Appalachians and Rockies .


There are three distinct mountain ranges within the U.S. Interior Highlands:

The U.S. Interior Highlands is dominated by temperate broadleaf and mixed forests . Three national forests are located here: The Ouachita National Forest in Arkansas and Oklahoma; the Ozark-St. Francis National Forest in Arkansas; and the Mark Twain National Forest in Missouri.