Area 51 request filed in 2005, the CIA publicly acknowledged the existence of the base for the first time, declassifying documents detailing the history and purpose of Area 51. Area 51 is located in the southern portion of Nevada in the western United States, north-northwest of Las Vegas. Situated at its center, on the southern shore of Groom Lake, is a large military airfield. The site was acquired by the United States Air Force in 1955, primarily for the flight testing of the Lockheed U-2 aircraft. The area around Area 51, including the small town of Rachel on the "Extraterrestrial Highway", is
Area 51 of foreign technology aircraft continued and expanded throughout the 1970s and 1980s. Area 51 also hosted another foreign materiel evaluation program called HAVE GLIB. This involved testing Soviet tracking and missile control radar systems. A complex of actual and replica Soviet-type threat systems began to grow around "Slater Lake", a mile northwest of the main base, along with an acquired Soviet "Barlock" search radar placed at Tonopah Air Force Station. They were arranged to simulate a Soviet-style air defense complex. The Air Force began funding improvements to Area 51 in 1977 under project SCORE EVENT. In 1979, the CIA transferred