Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

This frequently-photographed waterfall takes only a short hike to visit.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

A monument to the art of slicing people open.

A beautiful geyser under environmental threat.

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

The first declared National Monument in the United States.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

A dilapidated dock tells the story of Titanic's missed arrival.

Towering basalt columns, a creation of fire and ice.

A tiny theater hidden in an alley plays a constant stream of short silent films for anyone willing to peer through the peephole.

Here, at the "world's longest art gallery," you'll find forty miles of ancient petroglyphs and pictographs.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

Paranormal experiences in this hotel's room 217 led Stephen King to write "The Shining."

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

Stroll through a wonderland of stupendous moss-covered trees.

A trash dump made beautiful by nature's power.

A 100-year-old purveyor of curiosities, curios, and kitsch featuring mummies, shrunken heads, and a Fiji Mermaid.

A winding path built in secret on the edge of the continent.

This Boston medical museum features the skull of the famous medical case of Phineas Gage.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.