Bighorn Canyon National Recreation Area was established by an act of Congress on October 15, 1966, following the construction of the Yellowtail Dam by the Bureau of Reclamation. This dam, named after the famous Crow chairman Robert Yellowtail, harnessed the waters of the Bighorn River and turned this variable stream into a lake. Archeological and historical resources complement the natural scene. About one third of the area is within the Crow Indian Reservation.
The Bighorn River is a tributary of the Yellowstone, approximately 461 miles (742 km) long, in the western United States in the states of Wyoming and Montana. The river was named in 1805 by fur trader François Larocque for the Bighorn Sheep he saw along its banks as he explored the Yellowstone River.
The upper reaches of the Bighorn, south of the Owl Creek Mountains in Wyoming, are known as the Wind River. The two rivers are sometimes referred to as the Wind/Bighorn. The Wind River officially becomes the Bighorn River at the Wedding of the Waters, on the north side of the Wind River Canyon near the town of Thermopolis. From there, it flows through the Bighorn Basin in North Central Wyoming, passing through Thermopolis and Hot Springs State Park. The Bighorn River has also been known as: Great Horn River, Le Corne, and Iisaxpúatahcheeaashisee (Apsáalookěi).
Through Monday, September 6th: 8:00 a.m. - 5:30 p.m. September 7, 2010 - May 15, 2011 8:30 a.m. - 4:30 p.m. ,From December 5, 2010 - March 26, 2011, the visitor center will be open five days a week from 8:30 a.m. - 4:30 p.m. Thursday - Monday. The visitor center will be closed on Tuesday and Wednesday.