Listed as a national intangible cultural heritage, Lanzhou waterwheel was invented by Duan Xu in Duanjiatan, Lanzhou, back in the Ming Dynasty and first built for irrigation purpose in Gulaohuang.
Duan was a jinshi (someone who passed all three examinations held by the government) in the second year of Emperor Jiajing reign of the Ming Dynasty. Duan once served as an imperial censor in Yunnan, a place of abundant water resources where wheels were used for irrigation.
Duan designed a waterwheel based on those wheels used in Yunnan after returning to his hometown. In 1556 (the 35th year of Emperor Jiajing reign), the first waterwheel was set up on the northern bank of Yellow River outside the Guangwu Gate. Over the past four centuries, Duan's invention has been constantly improved and has developed its own style. With solid establishment and steady operation, a waterwheel has the capacity to irrigate tens of thousands mu of farmlands day after day.