The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

A well-preserved Ancestral Puebloan ruin tucked beneath a desert cliff.

Bizarre lunar-like landscape with thousands of large stone "hoodoos."

Sandstone rock formations that look like they belong on the cover of a progressive rock album.

This rugged area of red rocks and arches is often considered one of the most beautiful places on Earth.

One of the world's oldest and most massive living organisms is a grove of quaking aspens.

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

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.

A house carved into a rock in the 1940s.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

Hidden in the Chihuahuan Desert resides an amazing collection of petroglyphs.

The home of famed war correspondent Ernie Pyle is now a library and museum dedicated to his memory.

A blacklight journey through a celestial art exhibit.

Natural sonic phenomenon comes with a grisly legend of murder and blood.

"I did this all while you were watching TV."

A cave's rare beauty held a cavernous secret hidden underground.

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

A clear blue swimming hole with hidden caves, still unexplored.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

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

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.