President Theodore Roosevelt was caught in the middle of the first major battle for wilderness preservation, over the building of Hetch Hetchy Dam in Yosemite National Park.
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.
Originally settled as a mail stop, Las Vegas changed from an Old West vacation town, to a mafia haven, to the "Atomic City" and "Sin City."
The coal miners' battle for dignity led to the largest armed insurrection since the American Civil War.
As the star attraction of Buffalo Bill's Wild West Show, Annie Oakley thrilled audiences around the world with her shooting feats. Part of the Wild West collection.
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.
It was the largest fire in American history: by the time it was all over, more than three million acres had burned and at least 78 firefighters were dead.
The epic battle waged over dinosaur fossils by rival paleontologists in the American West.
During the Great Depression, Americans built the Hoover Dam, one of the greatest engineering works in history.