The Yellow River has been recognized by Chinese as "the mother river". But in ancient times, people living by the Yellow River often suffered its floods. Xuzhou was one such city. Located by the after-bay of the Yellow River, Xuzhou suffered from Yellow River floods since the Han Dynasty until the Yellow River changed its course in 1855, the 5th Year of Xianfeng in the Qing Dynasty (清代咸丰五年).