Great Basin, a triangular plateau, covering the western part of Utah, nearly the whole of Nevada and part of California and Oregon, and extending into Idaho, lying between the Wahsatch and the Sierra Nevada Mountains. It stretches about 500 miles along the base of the triangle from east to west and 800 miles from north to south. It is traversed by mountain ranges and covered by many streams and lakes, mostly salt, that have no outlet, but either drain by evaporation or sink into the sands of the desert.
