Ancient water supply system of the old town of Lijiang, Yunnan Province, China

Lijiang City is located at 2,400 m altitude in the northwest of Yunnan Province, China. Lijiang's old town, with an area of 3.8 km2 and about 25,000 inhabitants, was inscribed on the UNESCO World Heritage List on 6 December 1997 noting in particular that it “possesses an ancient water supply system of great complexity and ingenuity that still functions effectively today.” In this paper, the water supply system of the Old Town of Lijiang is described, analyzed and then evaluated in light of challenges from modern developments.