Robert Marshall, Aldo Leopold and Howard Zahniser dedicated their lives to protect the shrinking American wilderness.
The life of the legendary photographer, known best for his black and white images of the wilderness of the American West.
In 1934, American polar explorer Richard Byrd became the first to experience winter in Antarctica's interior.
The contradictory history of a dam that became a statement of American power and prestige.
When an earthen dam broke without warning, a small city in Pennsylvania was swept away in a wall of water over 30 feet high.
President Theodore Roosevelt was caught in the middle of the first major battle for wilderness preservation in Yosemite National Park.
Vivid memories of those trapped in the terrifying temblor of 1906 that killed thousands of Californians.
Her 1963 warnings about the effects of pesticides and herbicides sparked a revolution in environmental policy.