Yibin is a prefecture-level city in the southeastern part of Sichuan Province, People's Republic of China, located at the junction of the Min and Yangtze Rivers. Its population is 4,472,001 inhabitants according to the 2010 census of whom 673,413 live in the built-up area. Human habitation of Yibin dates back at least 40,000 years. Yibin was established as a county in the Han dynasty (206 BC - AD 220). With the rapid expansion of Sichuan in Song (960 to 1279) times, it grew quickly, receiving its modern county name in 1114 and becoming the seat of the prefecture of Xu. In the Ming (1368-1644) and Qing (1644 to 1911/12) periods, it became Xuzhou superior prefecture, known to Europeans as Suifu. In 1912 it reverted to the status of a county as Yibin.