Long before guestbooks and hotels, frontier travelers signed their names on this rock face.

This rustic old building is said to be the most photographed barn in America.

This UFO landing strip was created by a charitable Wyoming city that was worried about residents of Jupiter.

Devilish landscape, once cinema home to giant alien bugs, now derelict roadside attraction.

This Yellowstone geyser may not shoot as high as the nearby Old Faithful, but it erupts for considerably longer.

An architect's childhood fantasy treehouse made real.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A beautiful geyser under environmental threat.

The first declared National Monument in the United States.

Spectacular views await visitors to this lake.

The oldest badlands in North America, Makoshika State Park takes it name from the Lakota words for broken land.

The last physical evidence of the Lewis and Clark trail is one of their autographs etched into this giant rock.

The only road through the heart of Glacier National Park.

This grave marks the final resting place of a legendary frontiersman... unless it doesn't.

The world's longest known cave system.

Constructed in 1676, this stone memorial is believed to be the oldest veteran's memorial in the United States.

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.

See just what life was like in a 19th-century prospecting town.

Train debris from the deadliest avalanche in United States history can still be found in the ravine where so many perished.

Home of the only civilian casualty at the Battle of Gettysburg.

This Art Deco service station has been providing tune-ups and turning heads for close to a century.

An American flag was erected for every day that passed during the Iranian Hostage Crisis.

Memorializing an American tragedy of massive proportions.