Guantanamo Bay Naval Base (also called GTMO and pronounced gitmo by the U.S. military because the airfield designation code is GTMO) is located on 45 square miles (120 km2) of land and water at Guantánamo Bay, Cuba, which the United States leased for use as a coaling and naval station in the Cuban–American Treaty of 1903 (for $2,000 until 1934, for $4,085 since 1938 until now). The base is on the shore of Guantánamo Bay at the southeastern end of Cuba. It is the oldest overseas U.S. Naval Base.