Harmony Hall, located in Fort Washington, Maryland, is managed by the United States National Park Service as part of the National Capital Parks-East system. It has been a National Park Service site since 1966. Harmony Hall is a  2 1⁄2-story Georgian country house built of red brick during the eighteenth century. It is surrounded by 65 acres (26 ha) of land on Broad Creek, a Potomac River tributary. The home has been listed on the National Register of Historic Places since 1980, at which time its condition was described as "excellent". As of January 2010, Harmony Hall is closed to the public.