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
Ohio State Route 51 Toledo and Sylvania across the Maumee River and on Monroe Street. U.S. Route 223 now officially ends at U.S. Route 23's interchange with State Routes 51 and 184 in Sylvania. State Route 51's interchange with the Ohio Turnpike was opened in 1997. Ohio State Route 51 State Route 51 (SR 51) is a northwest-southeast highway (signed north-south) in northwest Ohio. Its southern terminus is at U.S. Route 20 just south of Elmore, Ohio, and its northern terminus is at its interchange, along with State Route 184, at U.S. Route 23 in Sylvania, Ohio. Before an ODOT signage project in 2010,