The Great Basin is a large, arid region of the American West, bordered by the Rocky Mountains to the east and the Sierra Nevada mountain range to the west. The 200,000 square mile area covers most of Nevada and parts of Idaho, Utah, and California. The region is most commonly defined by its waterflow: water falling on the Great Basin never reaches the ocean, but ends up deposited in the region's lakes.
The Great Basin is famous for its Salt Flats, where numerous landspeed records were broken, and for the Great Salt Lake.
The Great Basin is part of the Basin and Range Province.