Chongqing, formerly known as Chungking, is a major city in southwestern mainland China and one of the five national central cities. Administratively, it is one of the People's Republic of China's four direct-controlled municipalities (the other three are Beijing, Shanghai and Tianjin), and the only such municipality in western China. The municipality was created on 14 March 1997, succeeding the sub-provincial city administration that was part of Sichuan Province. In 2007, the municipality of Chongqing had a population of 31.4 million. It has jurisdiction over 19 districts, 17 counties, and four autonomous counties. With an area of 82,300 km² (31,800 mi²), it is the largest direct-controlled municipality, larger even than one province and an autonomous region, as well as Taiwan. It is possibly the world's largest municipality by population and one of the largest by area.