Dujiangyan Irrigation System

2,300-year-old irrigation system on the Min River. Still in use. UNESCO-listed jointly with Mt Qingcheng. Engineering rather than architecture, but one of the great works.

The Dujiangyan irrigation system was constructed in 256 BCE by Li Bing, a Qin-state engineer. By splitting the Min River with a Levee-and-Mouth (Yuzui) channel, the system delivers irrigation water to the Chengdu Plain without dams — the first major water-management work in human history that did not block the river. The system is still operational, watering 660,000 hectares. UNESCO-listed in 2000 jointly with Mt Qingcheng. Day-trip from Chengdu; combine with Mt Qingcheng (Daoist mountain) and the Dujiangyan Panda Base.