Sichuan (Chinese: 四川) is a province in Southwest China with its capital in Chengdu. The current name of the province, "四川", is an abbreviation of "四川路" , or "Four circuits of rivers", which is itself abbreviated from "川峡四路" , or "Four circuits of rivers and gorges", named after the division of the existing circuit into four during the Northern Song Dynasty.Sichuan, within its present borders, consists of two very geographically distinct parts. The eastern part of the province is mostly within the fertile Sichuan basin (which is shared by Sichuan with the now-separate Chongqing Municipality). The western Sichuan consists of the numerous mountain ranges forming the easternmost part of the Tibetan Plateau, which are known generically as Hengduan Mountains. One of these ranges, Daxue Shan, contains the highest point of the province - Gongga Shan, 7,556 meters tall.Lesser mountain ranges surround the Sichuan Basin from north, east, and south. Among them are the Daba Mountains, in the province's northeast.Plate tectonics formed the Longmen Shan fault, which runs under the north-easterly mountain location of the 2008 earthquake.The Yangtze River and its tributaries flows through the mountains of western Sichuan and the Sichuan basin; thus, the province is upstream of the great cities that stand along the Yangtze River in the central and eastern China, such as Chongqing, Wuhan, Nanjing and Shanghai. One of the major tributaries of the Yangtze within the province is the Minjiang River of central Sichuan, which joins the Yangtze at Yibin.Due to the great difference in the terrain, the climate of the province is highly variable. The Sichuan Basin (including Chengdu) in the eastern half of the province experiences a subtropical monsoon climate with long, warm to hot, humid summers and short, mild to cool, dry and cloudy winters, with China's lowest sunshine totals. The western areas have a mountainous climate characterized by very cold winters and mild summers, with plentiful sunshine. The southern part of the province, including Panzhihua, has a sunny, subtropical climate with very mild winters and hot summers.Sichuan borders Qinghai province to the northwest, Gansu province to the north, Shaanxi province to the northeast, Chongqing municipality to the east, Guizhou province to the southeast, Yunnan province to the south, and Tibet Autonomous Region to the west.