The great Altai, Tian Shan, and Kunlun mountain ranges enclose the region on the north, west, and south, respectively; a barren plateau lies to the west. Xinjiang's rivers, including the Tarim, Yarkant, Ili, Manas, and Hotan, rise in the mountains and flow from east to west. The level land, divided by the Tian Shan in central Xinjiang, comprises Dzungaria, a grazing region to the north, and the Tarim basin (Taklimakan), a vast desert to the south. Lop Nur, a largely dried-up salt lake in the Tarim basin, is the site of Chinese nuclear test explosions. Xinjiang has a dry continental climate with great extremes of winter and summer temperature. Rainfall is scant, seldom exceeding 10 in. (30 cm) annually.
Xinjiang is ethnically diverse, with mainly Muslim, Turkic-speaking Uigurs making up nearly half the population. There are also Hui, Mongolians, Manchu, dozens of other minority groups and, as a result of government-encouraged migration and development, a growing Chinese population that roughly equals the Uigur population. Most people live along the borders of the Dzungaria and the Tarim basin. Xinjiang Univ. is in Ürümqi.