The Columbia River is the dominant river system of the Northwest United States. It is a river of many uses--hydropower, fisheries, and irrigation--and was known by many names--Columbia's River, the Big River, and even River in the Chickadee Territory. It is the fourth-largest river by volume in North America, draining parts of seven states and the province of British Columbia. Because of its unique location close to the ocean, its tall mountain ranges, its steep drop from headwaters to the ocean, its deep and solid canyon, and its huge volume of clear, cold water, the Columbia River evolved as one of the great salmon and hydropower rivers of the world. And therein lies the chief paradox of the Columbia--the conflict of its natural history with its human history. Today, the river is an "organic machine," in the words of historian Richard White, part nature, part machine. This book briefly explores the natural and human histories of the river through photographs from historical archives, government agencies, and personal collections.