Wind River Indian Reservation is an Indian reservation shared by the Eastern Shoshone and Northern Arapaho tribes of Native Americans in the central western portion of the U.S. state of Wyoming. It is the seventh-largest Indian reservation by area in the United States, encompassing a land area of 3,473.272 sq mi (8,995.733 km²), or land and water area of 3,532.010 sq mi (9,147.864 km²), encompassing just over one-third of Fremont County and over one-fifth of Hot Springs County. The reservation is located in the Wind River Basin, and is surrounded by the Wind River Mountain Range, Owl Creek Mountains, and the Absaroka Mountains. The 2000 census reported a population of 23,237 inhabitants. The largest town is Riverton. Headquarters are at Fort Washakie. Also home to the Wind River Casino, Little Wind Casino, 789 Smoke Shop & Casino (all Northern Arapaho) and the Shoshone Rose Casino (Eastern Shoshone), which are the only casinos in Wyoming.