President Theodore Roosevelt was caught in the middle of the first major battle for wilderness preservation in Yosemite National Park.
The American effort to relieve starvation in Soviet Russia in 1921 during the worst natural disaster in Europe in 500 years.
In 1934, American polar explorer Richard Byrd became the first to experience winter in Antarctica's interior.
Robert Marshall, Aldo Leopold and Howard Zahniser dedicated their lives to protect the shrinking American wilderness.
The journey of Prince Maximilian, German naturalist, and artist Karl Bodmer, who explored the Mississippi River area from 1832-1834.
Before radar had been invented a devastating hurricane hit America, surprising residents of the East Coast and killing more than 600 people.
The New Deal program CCC put three million young men to work in camps across America.
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.