Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

The mysterious round rocks of Schooner Gulch.

Race through the maze, get your name on the sign.

A valley of unique erosion patterns lends to a view like nothing on Earth.

Charles Dickens was not a fan of the ghastly wall dressings in this 6th century church.

A former insane asylum despised by Nelly Bly and Charles Dickens is now fashionable apartments.

On Japan's Tashirojima Island, cats are king.

An unrealized dream to wirelessly electrify the entire Earth.

For nearly 2,000 years this church has been waging war on local snakes by importing cats.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

This massive subterranean fissure is known as the "underground Grand Canyon."

These termites have an large and deadly abode—impressive by day, dazzling by night.

A church of bones, decorated with 40,000 human skeletons.

Hanging over one of Japan's "hidden valleys," these vine bridges must be remade every three years.

This large round boulder is said to emit spiritual power, but it may just be magnets.

A small but industrious mining operation that allows visitors to touch precious gems while they are still in the rock.

North Central Florida's largest flea market and a weekend roadtripper's dream.

Silver in the hills led to the speedy creation of this boom town and a lack of it saw the town abandoned nearly as quickly.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

The haunting, dilapidated remains of a former poorhouse on Staten Island's Greenbelt.

The land is home to swimming ponies and a legendary 18th-century treasure.

A crumbling Beaux Arts monument to the Bay Area's age of rail.

A fake mine that was made using real mining techniques which is also used as a community center.

These eclectic homes nestled into the cliffs of a Caribbean island were built entirely from scavenged materials.