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 the judge, the land that overlooked the base was taken to address security and safety concerns connected with their training and testing. The amount of information the United States government has been willing to provide regarding Area 51 has generally been minimal. The area surrounding the lake is permanently off-limits to both civilian and normal military air traffic. Security clearances are checked regularly; cameras and weaponry are not allowed. Even military pilots training in the NAFR risk disciplinary action if they stray into the exclusionary "box" surrounding Groom's airspace. Surveillance is supplemented using buried motion sensors. Area 51 is a