List of the oldest buildings in Washington, D.C.

This article lists the oldest extant buildings in Washington, D.C., including extant buildings and structures constructed prior to and during the United States rule over Washington, D.C. Only buildings built prior to 1820 are suitable for inclusion on this list, or the building must be the oldest of its type. In order to qualify for the list, a structure must: be a recognizable building (defined as any human-made structure used or intended for supporting or sheltering any use or continuous occupancy); incorporate features of building work from the claimed date to at least 1.5 metres (4.9 ft) in height and/or be a listed building.

Source: Wikipedia — List of the oldest buildings in Washington, D.C. (CC BY-SA 4.0)