The Fort Kent Blockhouse is located at the confluence of the Fish River and the St. John River in Fort Kent, Maine. The blockhouse is the only fortification relating to the "Bloodless" Aroostook War of 1838-1839, and the border dispute between Great Britain and the United States. The signing of the Webster-Ashburton Treaty in 1842 settled the boundary dispute between Maine and New Brunswick and reduced the need for a fort, although federal troops remained there until 1845 to protect Maine’s and the United States’ interests in the region.

The blockhouse is a two-story structure. Its walls are built of square-hewn cedar logs, some of which measure over 19 inches in width. It is an excellent example of early 19th-century military architecture.

The blockhouse serves as a museum and is maintained by local Eagle Scouts in cooperation with the Bureau of Parks and Recreation, Maine Department of Conservation. The state-owned blockhouse is on the National Register of Historic Places as well as being a National Historic Landmark.