Also known as Groom Lake, Watertown, Dreamland and the Directorate for Development Plans Area.
It is a military facility in southern Nevada. Inside the enormous (4687 miles2) Nellis Bombing and Gunnery Range, a Air Force base there is a 60 mile2 block of land, sharing a border with the Nevada Test Site, at the centre of which is a large base. It was only acknowledged by the government in 1995 in order to exempt it from Federal, State, and local environmental laws.
The site was set up in the 1950s for testing of the U-2 spy plane, due to its remoteness, existing facilities and the presence of a large dry lake bed for landings (the Groom Lake of the name). It is the traditional testing ground for experimental aircraft (Skunk Works) before they are publicly acknowledged, apparently including the SR-71 Blackbird and F-117 Nighthawk.
See also Area 19.