Painted Desert (Arizona) plateau's south border the Mogollon Rim, the north border of the Arizona transition zone. Owing to the strong rain shadow of the Mogollon Rim, the Painted Desert has a cold desert climate (Köppen "BWk"), with hot, dry summers and cold, though virtually snow-free winters. The annual precipitation is the lowest in northern Arizona and in many places is lower even than Phoenix. Much of the region is accessible only by foot or unpaved road though major highways and paved roads cut across the area. The towns of Cameron and Tuba City, both on the Navajo Nation, are two major settlements.
Western Desert (Egypt) Nile valley. To the south, beyond the Bahariya oasis lies the Black Desert, an area of black volcanic hills and dolerite deposits. Beyond this, north of Farafra, lies the White Desert, an area of wind-sculpted chalk rock formations, which give the area its name. To the south of Kharga the plateau rises towards the Gilf Kebir, an upland region lying astride the Egypt-Sudan border and home to pre-historic sites such as the Cave of Swimmers. In the south-west, near the point where the borders of Libya, Sudan and Egypt meet, is an area of desert glass, thought to have been