The Marquesas Keys form an uninhabited island group about west of Key West, 4 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. The total area, including the lagoon, measures . The land area, according to the United States Census Bureau, is (exactly 6,579,703 m²), the water area (165,744 m²), giving a combined area of (6,745,447 m²), not counting water areas with connection to the open sea, but including small landlocked lakes on the Keys. The group is located at coordinates .