A petite castle folly in the English countryside.

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

16,500-acre ranch filled with American heritage, geological wonders, and a giant pile of tires is the crown jewel of an intriguing tug-of-war.

This floating cinema brings new meaning to the phrase "going out" to the movies.

Half of a waterfall goes into the river while the other half seems to disappear.

More than 5,000 contemporary and "historic" mustards from around the world.

Rock-hewn monastery complex with hundreds of cave structures tucked away into the mountainside.

The second-deepest known cave on Earth, hidden in an extremely remote mountain region.

Most prolific publishing house in the 1600s open to the public.

Ancient rock-hewn town that witnessed key events of Georgian history.

Dive bar built out of the remains of a whaling ship.

A Boeing mechanic and his wife leave a whimsical, stone sculptured garden as their legacy.

Mind-blowing carvings and fantasy ice scenes grace the largest year-round ice environment in the world.

Hungarian mummies in beautiful painted coffins.

This mountaintop lake bubbles and steams in a perpetual boil, thanks to its direct link to the Earth's interior.

Go inside to really appreciate this 500-year-old technological masterpiece.

A psychological self-portrait in the form of a giant, segmented head.

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

A 1950s eccentric's vision of Eden preserved as a hiking trail.

An alchemist's "magic door" stands in the middle of a Roman park.

Abandoned bridge hidden deep in the San Gabriel Mountains.

A store that sells all manner of bones, insects, and animal curiosities.

Thousands of well-dressed mummies below a monastery.