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Dujiangyan Irrigation System
Dujiangyan, a 2,300-year-old marvel of ancient engineering, channels the Minjiang River to irrigate Chengdu Plain and prevent floods. Built in 256 BCE by Qin Dynasty governor Li Bing and his son, it’s the world’s oldest operational water-control system, designated a UNESCO World Heritage Site in 2000. Without dams, it harmoniously divides water into irrigation canals using natural topography, feeding 668,700 hectares of farmland and inspiring modern hydrology. A testament to sustainable innovation, it’s equally revered for its serene riverside temples and pagodas.