Chongming, formerly known as Chungming, is an alluvial island at the mouth of the Yangtze River in eastern China covering as of 2010. Following its growth in the 20th century, it is now the 2nd-largest island of People's Republic of China. Together with the islands Changxing and Hengsha, it forms Chongming County, the northernmost area of the provincial-level municipality of Shanghai. At the time of the 2010 Chinese census, its population was .