Changzhou is a prefecture-level city located in southern Jiangsu province, China. It is situated on the southern bank of the Yangtze River and shares borders with Nanjing to the west, Zhenjiang to the northwest, Wuxi to the east, and Zhejiang province to the south.
Historically, the city has been known by several names, including Yanling, Lanling, and Jinling. As of the 2020 census, the population of the Changzhou Municipality was recorded at 5,278,121. The city is also noted as the birthplace of Zhou Youguang, who is credited with creating the pinyin romanization system.