The Zhuoshui River, also known as the Choshui or Jhuoshuei River, is the longest river in Taiwan. It spans a total length of 203 kilometers (126 miles).
The river originates in Nantou County and flows toward the western border of the county. From there, it serves as the boundary between Yunlin County and Changhua County. Geographically, the Zhuoshui River functions as an unofficial boundary dividing the north and south regions of Taiwan.