National Historic Site (NHS) and National Historical Park (NHP) are designations for officially recognized areas of nationally historic significance in the United States. They are usually owned and managed by the federal government. An NHS usually contains a single historical feature directly associated with its subject, while an NHP is an area that generally extends beyond single properties or buildings to include a mix of historic and later structures and sometimes significant natural features.[1]
As of 2024, there are 63 NHPs and 85 NHSes. Most NHPs and NHSs are managed by the National Park Service (NPS). Some federally designated sites are owned by local authorities or privately owned, but are authorized to request assistance from the NPS as affiliated areas.[2] One property is managed by the U.S. Forest Service, Grey Towers National Historic Site.[3]
Since October 15, 1966, all historic areas, including NHPs and NHSs, in the NPS are automatically listed on the National Register of Historic Places (NRHP). There are also about 90,000 NRHP sites, the large majority of which are neither owned nor managed by the NPS. Of these, about 2,600[4] have been designated at the highest status as National Historic Landmark (NHL) sites.