The Red Desert is a high altitude desert and sagebrush steppe located in south central Wyoming, comprising approximately 9,320 square miles (24,100 square kilometers). Among the natural features in the Red Desert region are the Great Divide Basin, a unique endorheic drainage basin formed by a division in the Continental Divide, and the Killpecker Sand Dunes, the largest living dune system in the United States. In the 19th century, the Oregon, California and Mormon Trails crossed the Continental Divide at South Pass, just north of the Red Desert. Today, busy Interstate 80 bisects the desert's southern region while gas field roads cross the desert.