No river communicates a more compelling history of South Asia than the Ganges. Stretching from the majestic Himalayas to the Bay of Bengal, the river has long been revered as a goddess, its sacred waters promising salvation to its millions of devotees. Over the centuries, the Ganges and its tributaries have also been a major natural resource for the highly developed states and societies that emerged in their basins, in recent times supporting a significant proportion of India’s huge population. A source of sustenance—and irrigation, transportation, and power—the Ganges story is about the fascinating and complex dynamics between its waters and religion, culture, economy, politics, and environment.