Fort Vancouver National Historic Site is a United States National Historic Site located in the states of Washington and Oregon. The National Historic Site consists of two units, one located on the site of Fort Vancouver in modern-day Vancouver, Washington; the other being the former residence of John McLoughlin in Oregon City, Oregon. The two sites were separately given national historic designation in the 1940s.[4] The Fort Vancouver unit was designated a National Historic Site in 1961, and was combined with the McLoughlin House into a unit in 2003.
http://en.wikipedia.org/wiki/Fort_Vancouver_National_Historic_Site