Eons ago, a rushing lava river formed this pristine passage through solid rock.

An abandoned facility that has become a place of ritualistic satanic worship, or so rumor has it.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

All of the 20 occupied houses in this mostly abandoned town feature some curious display of junk art.

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

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.

Giant pinnacles in the sun-scorched lands of Southern Utah have been nicknamed "white ghosts."

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

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

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

These aggressively sustainable art homes look like something out of 1970's science fiction.

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

A unique geological area spiked with wind-carved rocks that resemble teepees.

A Tucson museum and performance space full of found-object movable sculptures.

The Magical World of George Phar Legler.

Lyon, France is home to two remarkably preserved Roman theaters, one dating back to 15 BCE.

Lyon's miniature version of the Eiffel Tower was built as a statement in support of French secularism.

For hundreds of years, automatons moving to metallic music have been marking the passage of time.

Hundreds of hidden passageways weave through the old quarters of Lyon.

Self-built house and sculpture park where the creator can still be seen in a glass coffin.

Miniature art that tells an enormous story.

Monsters and miniatures are held in equal esteem at this wondrous museum.

House of vintage taxidermy and Steampunk sculptures in a quiet Pittsburgh neighborhood.

One of the world's largest model railroads is a mind-boggling achievement.