AREA 51, sometimes referred to as "Dreamland" or "Groom Lake", is a secret military facility located about 90 miles north of Las Vegas, Nevada. A block of land 6 miles north-to-south by 10 miles east-to-west, it is bordered by Nellis Air Force Base on the northwest, north, east, and south, and by the Nevada Test Site on the southwest. Although the government will not discuss its existence, many highly classified national defense projects have been conducted at AREA 51 since the 1950s and the airspace around the base is off-limits even to most military pilots. Spy planes such as the U-2, SR-71, YF-12A, and F-117A were developed there, as well as the technology associated with the Strategic Defense Initiative (aka "Star Wars"). AREA 51 is also the approximate location where scientist Robert Lazar claims to have worked for the U.S. government reverse-engineering the propulsion mechanism of a captured alien spacecraft. In the past, there were actually two viewpoints from which the public could legally view this secret facility -- from White Sides and Freedom Ridge -- but the Air Force closed down both locations in 1995. It is still possible to view the base, however, from a distant mountain, Tikaboo Peak. However, it requires a strenuous 1 1/2 hour hike from a remote dirt road to reach this vantage point.