An abandoned castle owned and ignored by Masons carries a cursed history.

A spectacular cave and a beguiling lake.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

World's first "penitentiary," meant to be humane, drove men insane.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

An emerald-green grotto just a short trip from Austin.

This zombie-themed restaurant stands out in the heart of corn country.

Even with only two residents and one building, this tiny Illinois town is famous for its burgers.

This abandoned prison castle has become an imposing gallery of graffiti art.

In the loving memory of a tragically deceased role-player this Illinois park is decked out with both dungeons and dragons.

Curious cave that stays a cool 56 degrees all year long.

Erosion and time have created a naturally-formed water park.

The artwork that Italians felt California didn't deserve.

This dark, quiet forest on the outskirts of San Diego is dense with rumor and lore.

Behind this beachfront shop lies a spectacular, colorful sea cave with an equally colorful past.

San Diego's most historic and haunted home.

A gothic palace of endless stalagmites and pseudoscorpions waits within one of the world's most beautiful caves.

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

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.

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

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

America's only nuclear missile silo open to the public.