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

This canyon is named for a unique geologic formation where the river vanishes underground near the mouth of the canyon and reappears farther down.

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

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.

A beautiful geyser under environmental threat.

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

This town is home to the world’s largest arch constructed entirely of elk antlers.

One of America's largest retail chains got its start in one of its most remote rural destinations.

Named for a prominent scout and explorer, this Wyoming state park encompasses a replica of an 1840s trading post, a 19th-century Army outpost, and early 20th-century automobile lodgings.

Mark Twain once stopped at this rest station during his journey to Nevada.

Surrounded by a hundred mile radius of billboards, Little America is a roadside attraction whose primary appeal is hospitality.

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

A local museum remembers one of the worst acts of anti-Chinese violence in American history.

This sandstone building is a relic of the Overland Trail.

This mining town boomed in the Atomic Age when uranium was gold, only to be abandoned when the industry collapsed.

A devilishly named gorge that was a sign of salvation for many pioneers.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

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

The first declared National Monument in the United States.

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

A cemetery housing wild west legends in South Dakota.

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.