The Marquesas Keys form an uninhabited island group about 20 miles (32 km) west of Key West, four miles (6 km) in diameter, and largely covered by mangrove forest. They are an unincorporated area of Monroe County, Florida, and belong to the Lower Keys Census County Division. They are protected as part of the Key West National Wildlife Refuge. The Marquesas were used for target practice by the military as recently as 1980.