世界屋脊
North of the Himalayas and east of the Karakorum/Pamirs is the vast Tibetan Plateau, the largest and highest plateau in the world, also known as the "Roof of the World." The plateau has an average elevation of 4,000 meters above sea level and covers an area of 2.5 million square kilometers, or about one-fifth of China's land mass. In the north, the plateau is hemmed in by the Kunlun Mountains, which extends eastward from the intersection of the Pamirs, Karakorum and Tian Shan.