This short bridge is the only thing connecting a tiny Irish island to the mainland.

Northern Ireland's Brobdingnagian stepping stones.

A 30-acre garden inspired by the principles of modern physics.

America's most famous piece of self-built architecture.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Historic medieval fortified city in southwest France.

Gods clash with machines in a power plant regenerated as a museum.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Venice's island of the dead.

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

The middle finger of modernity.

The largest and most famous wax anatomical collection anywhere in the world.

A large grotto built in the 16th century amidst Florence's famous Boboli gardens.

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

The oldest operating pharmacy in the world features 800-year-old recipes.

One of the oldest living oak trees in the Southeast.

Enormous lake at the bottom of a unique cave system.

The world's largest set of the ten commandments lay nestled in the heart of the Great Smoky Mountains.

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.

This structure among the trees was the result of divine inspiration.

The ghostly remains of an accidental sea.

Version of the French Riviera destroyed by the sea.