The Great Basin was a large, arid region of the western United States on Earth. Its boundaries depended on how it was defined. Its most common definition was the contiguous watershed, roughly between the Wasatch Mountains, in Utah and the Sierra Nevada, that had no natural outlet to the sea. Therefore it was endorheic. The Great Basin Desert was defined by the extent of characteristic plant species, and covers a somewhat different (and smaller) area. The Great Basin Culture Area, home to several Shoshonean Great Basin tribes, extended further to the north and east than the hydrographic basin. The Basin and Range Province was a geologic region that was most recognizable in the Great Basin but extended well into the Sonoran and Mojave Deserts. (TLE novel: Serpents Among the Ruins)