Three centuries ago, the Los Angeles River meandered through marshes and forests of willow and sycamore. Today, the river is made almost entirely of concrete. Chain-link fence and barbed wire line its course. For much of its course, the river looks more like a deserted freeway than a river.

The river's contemporary image belies its former character and its importance to the development of Southern California. Los Angeles would not exist were it not for the river, and the river was crucial to its growth. Recognizing its past and future potential, a potent movement has developed to revitalize its course. The Los Angeles River offers the first comprehensive account of a river that helped give birth to one of the world's great cities, significantly shaped its history, and promises to play a key role in its future.

Blake Gumprecht is an assistant professor of geography at the University of New Hampshire.