Yuxi was once the core area of Yunnan Province during the Previous Qin Dynasty (period before 221BC). In the Western Han Dynasty (206BC-24AD), it became a county of Yizhou Shire. The following dynasties witnessed the continuous separations and unifications of the area. It was not until 1997 that Yuxi became a prefecture-level city of the Republic of China. Yuxi is in the west edge of Yunnan-Guizhou Plateau, with complex geographic features including mountains, valleys, lakes, plateaus and basins. Fuxian Lake is China's second deepest lake.