The southernmost of Huai'an's county-level divisions, it borders the prefecture-level cities of Suqian, Jiangsu, to the north and Chuzhou, Anhui, to the south and west.

It was the hometown of Zhu Yuanzhang's family, which fled to Fengyang before his birth and rise to power as the Hongwu Emperor of the Ming.

He subsequently erected the expansive Ming Zuling tomb nearby, where veneration could be offered to his grandfather, great-grandfather, and great-great-grandfather, all posthumously elevated to the dignity of honorary emperors.

Its silt blocked the previous course of the Huai and caused Hongze Lake to grow enormously, swallowing both Sizhou and Ming Zuling tombs.

After the establishment of the People's Republic of China, Xuyi and Sihong were both moved from Anhui to Jiangsu in 1955 to allow for unified administration for the entire area around Hongze Lake.