Old Danish castle immortalized in Shakespeare's Hamlet.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Tiring of digging out the door to this church for every service, it was eventually abandoned to the sands.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

Across the Pacific in a raft, a museum dedicated to Thor Heyerdahl's now legendary expedition.

Housing the famous Norwegian ice-defying 19th century polar exploration ship.

Home to three historic ships from the age of Vikings.

This handsomely carved wooden church is more than 800 years old.

An intricately carved Viking church overlooks a glistening fjord.

Longest road tunnel in the world features an air treatment plant and the illusion of daylight.

Walk behind a 50-meter-high waterfall.

The grounds and buildings of an old wood pulp mill have been transformed into an innovative art park and museum.

A serpentine highway twists and turns over the treacherous Norwegian Sea.

Thousands of years of crashing waves gave this mushroom-shaped rock its svelte figure.

A favorite with sightseers, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

St George's Leprosy Museum depicts the gruesome afflictions of those suffering from the disease.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

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

This bronze boar's snout has been rubbed to a golden sheen by visitors seeking good fortune.

The middle finger of modernity.

Standing in a state of "arrested decay," this ghost town allows for a detailed peek into Gold Rush life in an unusually harsh climate.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.