High on a granite cliff in South Dakota's Black Hills tower the huge carved faces of four American presidents: George Washington, Thomas Jefferson, Abraham Lincoln, and Theodore Roosevelt.
Her 1963 warnings about the effects of pesticides and herbicides sparked a revolution in environmental policy.
John Wesley Powell's epic journey into the unknown Grand Canyon was filled with adventure as his team mapped the Colorado River for the first time.
The most daring and innovative accomplishment at the turn of the 20th century.
President Theodore Roosevelt was caught in the middle of the first major battle for wilderness preservation in Yosemite National Park.
Native Alaskans, oil company representatives, environmentalists, politicians, and others tell the story of the 800-mile pipeline.
The life of the legendary photographer, known best for his black and white images of the wilderness of the American West.