Aerial view of Sedan Crater, the result of the underground detonation of a 100 kiloton nuclear bomb at the Nevada Test Site on July 6, 1962. The crater is 98 metres (320 feet) deep and 390 metres (1280 feet) in diameter. The explosion occurred 194 metres (635 feet) underground and displaced around 12 million tonnes of earth. The Nevada site is located some 65 miles north-west of Las Vegas and covers over 800,000 acres. It is surrounded on three sides by large tracts of land belonging to the Nellis Air Force range.