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

It houses the remains of a 17th-century version of the Titanic.

"There's nothing there," and other lies the KGB told us.

The mark of the Devil's horns on a marble column in Milan.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

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

An ancient Egyptian temple in the middle of Madrid, Spain.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

It is against the law to obstruct the view from the top of this English burial mound.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A student driver's nightmare.

Eighty million natural history specimens call this gargantuan museum home.

The taxidermied remains of a once-great parrot.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

The remains of Alfred Nobel's first nitroglycerine factory can still be found on the shores of a Swedish bay.

This homeless brass fox tugs at your heartstrings from the foot of a Stockholm bridge.

Now a hotel, this former bank was the site of a robbery that spawned a psychological phenomenon.

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

Home to three historic ships from the age of Vikings.

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.

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