This art installation at an abandoned lipstick factory has distinct anti-capitalist vibes.

A New York–based physician returned home to Spain to build his own elaborate monument to Christopher Columbus.

This abandoned mansion has a window for every day of the year, and is a temple for ghost hunters.

A beautifully well-preserved ancient Roman villa.

A limestone grotto where daylight filters in from below and turns the water a beautiful turquoise. Also home to a small underwater nativity scene.

Amalfi's pre-industrial history is slowly being engulfed by the lush vegetation of the Ferriere Valley.

Beautiful views and Roman-style statues on the Italian coast.

According to the legend, this structure was built in a single night with the help of the devil.

For centuries no one knew there were hundreds of bones and precious artwork hidden beneath this Swiss church.

The world's largest private telescope collection hides in a secret wing of a Dutch auto museum.

A curious cave church carved into the face of a cliff.

This virtually windowless mass of smooth concrete is the only Catholic church in the city.

Its frescoes depict the likeness of Marshal Tito, Karl Marx, and Friedrich Engels burning in hell.

The tangled roots of a giant banyan tree have fully reclaimed the ruins of this abandoned warehouse.

Flying high over the small island of Zákynthos is a giant tribute to the mainland.

Science meets wall art to highlight the beauty of famous mathematical equations.

One of only two commuter aerial tramways in the United States.

A huge musical instrument played by the ocean.

This scenic Icelandic lava flow is named for a pair of Berserkers who were murdered, according to a famous Saga.

Twice a year, visitors can tour the desolate site that birthed the Atomic Age.

Each spring, a dreamlike carpet of bluebells overtakes the forest floor.

This 170-year-old Swiss guesthouse built into the side of a mountain is best accessed by a cable car.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

The remains of a doomed Antarctic plane, buried beneath layers of ice and snow, await those willing to do a bit of digging.