Sitting on an Italian hilltop is this surreal fortress built by the mad inventor of electrohomeopathy.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

This chilly Canadian hotel has a four-month lifespan due to the unusual material it's made of.

An architect's childhood fantasy treehouse made real.

Hidden deep in the Guatemalan jungle is a turquoise paradise of natural pools, caves, and waterfalls.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

Hidden in a secluded Greek cove is a pristine beach marred only by the rusting smuggler's hulk stranded on its shores.

A Romanesque tower appears when water levels drop.

Mirrors and glass shards cover every inch of this arrestingly beautiful mosque.

Two stunning 17th-century libraries and a cabinet of curiosities.

This giant boulder is pinched over a 1000-meter abyss by two mountains.

One of the Eight Wonders of Kansas and the first official National Natural Monument these stark formations look like nature's Stonehenge.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

The curious underground history of keeping Paris clean.

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

This stunning gothic ruin was a casualty of the Indiana steel industry crash.

Reputedly haunted sandstone necropolis with exquisite stone carvings.

For more than 40 years this Barnum-inspired half-fox, half-woman has been telling fortunes from her cage in a Pakistani zoo.

A memorial to a Swedish hockey player's "encounter" with aliens.

A former taxidermist has turned his old shop into a folk art mecca.

One native village in Bali lays their dead at the foot of a holy tree whose natural fragrance seems to hide the stench as the bodies decompose.

Watch the newest land on the planet form before your eyes.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.