section_path: Main sights/World natural and cultural heritage sites/Dujiangyan Irrigation System
section_name: Dujiangyan Irrigation System
paragraph_text: Dujiangyan Irrigation System
  
  The Dujiangyan Irrigation System (58 km (36 mi) away from downtown Chengdu) is the oldest existing irrigation project in the world with a history of over 2000 years diverting water without a dam to distribute water and filter sand with an inflow-quantity control. The system was built by Libing and his son. The irrigation system prevents floods and droughts throughout the Plain of Chengdu.