Chongqing, alternately romanized as Chungking, is a municipality in southwest China.
Administratively, it is one of the four municipalities under the direct administration of the central government of the People’s Republic of China (the other three are Beijing, Shanghai and Tianjin), and the only such municipality located deep inland. The municipality of Chongqing, roughly the size of Austria, includes the city of Chongqing as well as various discontiguous cities. Due to a classification technicality, Chongqing municipality can claim to be the largest city proper in the world—though it does not have the world’s largest urban area.
During the Republic of China (ROC) era, Chongqing was a municipality located within Sichuan Province. It served as its wartime capital during the Second Sino-Japanese War (1937–1945). The current municipality was separated from Sichuan province on 14 March 1997 to help develop the central and western parts of China. The Chongqing administrative municipality has a population of over 30 million. The city of Chongqing, comprising 9 urban and suburban districts, has a population of 8,750,000 as of 2018. According to the 2010 census, Chongqing is the most populous Chinese municipality, and also the largest direct-controlled municipality in China, containing 26 districts, eight counties, and four autonomous counties.
The official abbreviation of the city, “Yú” (渝), was approved by the State Council on 18 April 1997. This abbreviation is derived from the old name of a part of the Jialing River that runs through Chongqing and feeds into the Yangtze River.
Chongqing has an extensive history and a rich culture. As one of China’s National Central Cities, it serves as a financial center of the Sichuan Basin and the upstream Yangtze. It is a major manufacturing and transportation center; a July 2012 report by the Economist Intelligence Unit described it as one of China’s “13 emerging megalopolises”. Chongqing is ranked as a Beta (global second-tier) city. Chongqing is one of the top 100 cities in the world by scientific research outputs as tracked by the Nature Index, and home to several notable universities, including Chongqing University, Southwest University, Chongqing University of Posts and Telecommunications, Southwest University of Political Science and Law and Chongqing Normal University.
Source:  Chongqing – Wikipedia