Qanats are ubiquitous, yet unseen, and a clever way to create streams where none exist in nature. For 3,000 years, they have made life possible in impossible places and still sustain life and livelihoods in many countries today. After 30 years of field research, Dale Lightfoot provides the first comprehensive study of the qanat and sheds new light on their unique locations and distribution, their origins and history, their ecology, current status and use. Qanats are remarkably engineered underground aqueducts, using gravity to bring water to villages and towns where reliable flowing surface water is scarce or absent. Although an ancient technology, more than 46,000 of them still flow around the world today, with their sustainable nature making them a focus of renewed interest. Richly illustrated with images and a series of original maps, this is the most complete record to date of the locations and distribution of qanats worldwide, including examples from the Middle East, North Africa, Europe, Central Asia, China, India, Mexico and South America.