Doncram is a Wikipedia Commons user who has posted photos of historic sites in the United States, from HABS or taken by self.
Copyright of National Park Service website photos 
Copyright of photos in the U.S. National Park Service webpages are especially difficult to interpret. Specifically all photos within their PDF Focus system, both public domain and non-public domain ones are labelled by a known, general system error as "Public domain".This error in labelling has been specifically acknowledged in correspondence multiple times. See Wikipedia:WikiProject National Register of Historic Places#some but not all National Park Service photos are public domain. The actual policy is this disclaimer, which states "Not all information on this website has been created or is owned by the NPS. If you wish to use any non-NPS material, you must seek permission directly from the owning (or holding) sources." Their own mislabelling does not change the status of copyrighted photos which they display.