"Polynesia on the Plains."

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

An apocalyptic seismic event creates a deadly chain reaction that ends with a 6-mile long lake developing within weeks.

A rapidly disappearing glacier filled with extinct grasshoppers, perfectly preserved in the ice.

This beautiful ancient site is dotted with perforated sandstone pillars considered sacred by some Native American groups.

The only road through the heart of Glacier National Park.

Mining town from the late 1890s, once home to Calamity Jane.

The rocks of a certain area of Butte, Montana give off a musical ring when hit.

New fungal and bacterial species call this deadly lake home.

This amazingly preserved Gold Rush town is a historian's dream.

At the time of its completion, it was the tallest dam in the world.

Around half a million years ago, these magnificent columnar basalt cliffs were formed from cooling lava.

The crumbling structure is a rare surviving relic of the area's bygone mining industry.

Dance on a hand-hewn log floor padded with bouncy boxcar springs at a saloon built in 1883.

This shallow pit was once used to send over 20,000 buffalo plummeting to their death.

The easiest way to the highest point in Wyoming is only accessible via one hefty fee.

A small town built on an abandoned airfield has former runways as streets and a bar and grill in an old airplane hangar.

No Gordon Lightfoot song, only a barebones monument to greed.

This Wyoming town is fascinated by a particular mythical creature.

Population: 1.

A monument to the egos of two railroad magnates that fell into decline along with their careers.

A popular rock that acted as a waymarker for American pioneers.

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.