QingHai is situated in western China, in the Tibetan Plateau (Qing Zang Gaoyuan). It is one of China's least populated provinces. In the extreme east in the valleys of the upper Huang He (Yellow River) and its tributaries concentrates main population,agriculture and economic activity. To the west lie high mountains , arid plateaus and basins for nomadic herding predominates. Coal, petroleum, and iron ore are the main natural resources. At present are reserves of borax, salt, and phosphates in many large salt lakes. The capital, Xining (Sining), is the only large city. Chinese there occupy only about one-third of the population; Mongols, Tibetans, Hui (Chinese Muslims), and Kazaks are the largest ethnic minorities,but it still is the transportation and industrial center.For centuries Xining has been a gateway to Tibet and Central Asia, and major highways follow old caravan routes.