Area 51 the base extends further east. After leaving the restricted area, Groom Lake Road descends eastward to the floor of the Tikaboo Valley, passing the dirt-road entrances to several small ranches, before converging with State Route 375, the "Extraterrestrial Highway", south of Rachel. Area 51 shares a border with the Yucca Flat region of the Nevada Test Site, the location of 739 of the 928 nuclear tests conducted by the United States Department of Energy at NTS. The Yucca Mountain nuclear waste repository is southwest of Groom Lake. Groom Lake is a salt flat in Nevada used for runways of the
Oklahoma State Highway 51 March 25, 2008. In a first for the state of Oklahoma, the bridge, originally built in 1936, was sold to Payne County for $200,000 and transferred to a county road east of Stillwater, where it was installed over Council Creek. Like many in the Oklahoma state highway system, SH-51 has short spurs branching from it that bear the "51" number with a lettered suffix: Oklahoma State Highway 51 State Highway 51, abbreviated to SH-51 or OK-51, is a major state highway in Oklahoma. It runs for 333 miles (535½ km) east–west across the state, running from the Texas state line