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.
The journey of Prince Maximilian, German naturalist, and artist Karl Bodmer, who explored the Mississippi River area from 1832-1834.
Robert Marshall, Aldo Leopold and Howard Zahniser dedicated their lives to protect the shrinking American wilderness.
The epic battle waged over dinosaur fossils by rival paleontologists in the American West.
Her 1963 warnings about the effects of pesticides and herbicides sparked a revolution in environmental policy.
President Theodore Roosevelt was caught in the middle of the first major battle for wilderness preservation in Yosemite National Park.
The New Deal program CCC put three million young men to work in camps across America.