Mount Rushmore still disputed on the basis of the 1868 Treaty of Fort Laramie (see section "Controversy" below). Among American settlers, the peak was known variously as Cougar Mountain, Sugarloaf Mountain, Slaughterhouse Mountain, and Keystone Cliffs. It was named Mount Rushmore during a prospecting expedition by Charles Rushmore, David Swanzey (husband of Carrie Ingalls), and Bill Challis. Historian Doane Robinson conceived the idea for Mount Rushmore in 1923 to promote tourism in South Dakota. In 1924, Robinson persuaded sculptor Gutzon Borglum to travel to the Black Hills region to ensure the carving could be accomplished. Borglum had been involved in sculpting the
Mount Rushmore center, finished in 1957. These structures were part of the Mission 66 effort to improve visitors' facilities at national parks and monuments across the country. On October 15, 1966, Mount Rushmore was listed on the National Register of Historic Places. A 500-word essay giving the history of the United States by Nebraska student William Andrew Burkett was selected as the college-age group winner in a 1934 competition, and that essay was placed on the Entablature on a bronze plate in 1973. In 1991, President George H. W. Bush officially dedicated Mount Rushmore. In a canyon behind the carved faces is