The Mammoth Hot Springs Historic District in Yellowstone National Park comprises the administrative center for the park. It is composed of two major parts: Fort Yellowstone, the military administrative center for the park in the years immediately following its founding as the World's first national park, and now a National Historic Landmark, and a concessions district which provides food, shopping, services and lodging for park visitors.
Fort Yellowstone is a carefully ordered district of substantial buildings that clearly indicate their military origins. The Army managed the park from its establishment in 1872 to the founding of the National Park Service in 1904. The park today is administered from a former army building, now the Albright Visitor Center.
The concessions district contrasts with the military district, with a less formal arrangement and style and includes the Mammoth Hot Springs Hotel and Dining Room, a gas station and retail stores. The residential area includes houses designed by architect Robert Reamer.
The district is directly adjacent to the Mammoth Hot Springs thermal area, and is itself built on an ancient travertine terrace. The Grand Loop Road Historic District runs through the Mammoth district, and the North Entrance Road Historic District adjoins just to the north.