Rippling sand dunes frozen in the Arizona rock.

This quiet park's strange sedimentary spires were named after Kodak's color film.

Local lore holds that Butch Cassidy took an escape route through Red Canyon's sandstone hoodoos after an attempted murder.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

A stoic rock cairn is all that remains to remember one of the more brutal instances of frontier treachery in American history.

The hike through a narrow river flanked by the 2,000-foot-tall walls of Zion Canyon is one of the best in the world.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

The huge collection of paintings of the American West is one of Denver's best-kept secrets.

This graveyard contains markers and monuments dedicated to some of the darkest chapters in Washington's history.

Find out what it sounds like when doves cry at Prince's recording studio estate turned museum.

A diminutive plaque recalls the treetop sniper who almost killed Abe Lincoln.

At this Minnesota state park you can easily wade across the source of the mighty Mississippi.

A tiny red pebble marks what may be the quietest outdoor spot in the United States.

Hidden behind Lincoln's head is a 70-foot-long chamber containing enamel plates documenting American history, sealed in a teakwood box in a titanium vault.

Mysterious wreckage of a small plane has been lodged in this tree since at least 1971.

Despite his legacy of work in Spain, Cuba, and Florida, the larger-than-life writer's grave is a simple affair tucked in an Idaho cemetery.

The "Seinfeld" diner.

A crumbling staircase in upper Manhattan is all that remains of one of the most important sites in sports history.

A whimsical, but often overlooked clock in Park Avenue.

Relics given to a Manhattan church to avoid seizure by the Italian government.

This Wall Street bar was once a hub of revolutionary activity where Washington famously bid farewell to his troops.

A legendary speakeasy bookstore returns from the brink.

A terrific purveyor of natural history objects and curios.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.