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

A house filled to the brim with oddities and curiosities.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

An ethereal glowing blue ocean cave in Croatia.

A museum dedicated to the alleged Roswell Incident.

Tubing through a cave lit with glowworms is a magical underground experience.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

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

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

A Japanese concept restaurant that feels like a party thrown by the monsters in your closet.

A museum dedicated to the history and exploration of both popular music and science fiction.

Carnivorous plants, medieval aphrodisiacs, and the largest original wood structure glass conservatory in the western hemisphere.

A swing to dangle you off the very edge.

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

A fiery crater has been burning in the Karakum Desert since 1971.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

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

Cabaret where the show girls are all androids, and the patrons couldn't be more pleased.

Art from the latest counter-culture; kids who dye their hair blue and believe the future will be a post-apocalyptic water world.

A museum befitting the city responsible for supplying the majority of the world's LSD.

Furniture tries to escape an abandoned building in San Francisco.

A nondescript building that's been functioning as a speakeasy for nearly a century and a half.