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
Oklahoma State Highway 51 area. In Sand Springs, SH-51 crosses the Arkansas River with SH-97 before merging onto the Sand Springs Expressway (U.S. Highway 412/U.S. Highway 64). When this freeway ends at I-244 near downtown Tulsa, Highway 51 merges onto I-244 southbound only to exit one mile (1.6 km) later, where it overlaps US-64/US-75. This freeway is actually Interstate 444, but the interstate designation is not shown on signs. After one more mile, SH-51 leaves the interstate with US-64 and becomes the Broken Arrow Expressway, a freeway running northwest-southeast through Tulsa which is known as "The BA" by locals and local media. US-64 leaves