These ruins of a pre-Columbian cliff village are among the most beautiful and well preserved in New Mexico.

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

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

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

What was to be the world's most secure Cold War document vault ended up as just a few shallow caves.

A Hawaiian stairway to heaven—that you can't climb.

This massive boulder is either a unique rock formation created by glacial melt or a magic energy vortex.

A winding, cliffside stretch of road overlooking the Delaware River.

An indoor miniature village and labor of love for Laurence Geiringer, a model railroad enthusiast.

A field of nothing but boulders which resembles a giant's gravel driveway.

Behold the rickety wooden glory of the world's oldest operating roller coaster.

A macabre farm reserved part of its 222-acres for dead bodies, all in the name of science.

"Dark Sky Park" is heaven on Earth for astronomers, one of the rare U.S. locations with no artificial light pollution.

You can climb to the summit of Black Mountain, as long as you sign the waiver.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

In which a local geological marvel becomes a quaint roadside attraction.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

Manhattan’s Battery Park has a whimsical carousel full of spinning, glowing fish.

Town full of spiritualists, some of whom are mediums, is still in full swing after 130 years.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.