the National Park Service, Yellowstone National Park was established on March 1, 1872, as the world's first national park. Between 1872 and 1886, the park was administered by the Interior Department and was managed by a civilian superintendent with limited resources or legal authority to maintain and protect the park's natural features and wildlife, or to deal with poaching, vandalism and other destructive activities. Over the next decade, special interest groups such as concessionaires, railroad and mining interests attempted to commercialize and privatize park lands. The poorly funded Interior Department was unable to prevent degradation of the park and in some circumstances, was complicit with special interest groups. Senator George Vest led efforts to prevent railroads and other special interests from misusing the resource, and along with other members of Congress believed that only the military could effectively protect the park. A study of the situation and amendments to the Yellowstone Park Act proposed by Senator Vest resulted in the Sundry Civil Appropriations Bill of 1883 which allowed the Interior Department to transfer control of the park to the War Department, thereby protecting Yellowstone from schemes to commercialize the park. In August 1886, Lieutenant General Philip Sheridan sent Company M, 1st U.S. Cavalry to the Park, where they established Camp Sheridan, named after General Sheridan, at Mammoth Hot Springs. Camp Sheridan consisted of an arrangement of temporary facilities at the base of Capitol Hill just east of the Mammoth Hot Springs travertine terraces. None of the facilities that comprised Camp Sheridan remain as they were all removed over the years. Congress appropriated funds for the establishment of a permanent fort in 1891, and the Interior Department allocated land just north of Camp Sheridan for permanent facilities. Camp Sheridan was renamed Fort Yellowstone on May 11, 1891. The army continued to use Fort Yellowstone until they turned over control of the park and the fort to the newly formed National Park Service in October 1918. Fort Yellowstone is a National Historic Landmark District that has 40 contributing buildings, two contributing structures, and two contributing sites. The district was added to the National Register of Historic Places on July 31, 2003 for its significance in conservation, military, politics and government from 1888 to 1918. The fort, along with concessionaire facilities that were built after the National Park Service assumed management of the park, comprise what is collectively known as the Mammoth Hot