U.S. Interior Highlands

Geography

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

• The Ouachita Mountains of Arkansas and Oklahoma, which can be divided into a number of subranges including the mountains of the Arkansas River Valley (called the Frontal Ouachita Mountains); the highest point is Mount Magazine at 2,753 ft (839 m).
• The Boston Mountains of the Arkansas and Oklahoma Ozark Plateaus; the highest point is Wahzhazhe Summit (formerly known as Buffalo Lookout), at 2,561 feet (781 m), 3.4 miles (5.5 km) east of Pettigrew, Newton County, Arkansas. Wahzhazhe is the Osage people’s name for themselves in the Dhegiha language.
• The St. Francois Mountains of the Missouri Ozark Plateaus; the highest point is Taum Sauk Mountain at 1,772 ft (540 m).

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.