The Great Man-Made River Project is a network of pipes that supplies fresh water from vast underground aquifers to cities in the Sahara desert region of Libya. The 4,000 km underground pipeline system is the largest of its kind in the world. It supplies over 6.5 million cubic meters of water per day to populations across Libya from over 1,300 deep wells. The project was conceived in the 1960s and took decades to complete in five phases, costing $25 billion. It transformed Libya from a water-scarce country reliant on desalination to a fully self-sufficient producer and supplier of fresh water.