In Florence's great Duomo, a 26 foot fresco honors a mercenary famous for attacking Florence.

This strange bovine gargoyle is said to have been put in as a passive aggressive form of revenge.

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

Picturesque ruins once held off mighty armies.

The chefs at El Diablo use heat generated by an active volcano to cook the food.

Museum about life, death, and cannibalism in the Stone Age.

Historic medieval fortified city in southwest France.

Once thought to be the mysterious work of a witchy prophetess, a well with unusual properties turns objects into "stone".

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

The prototype for all Nazi concentration camps.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Go surfing on this urban wave, "hacked" by local surfers.

Dublin's "Dead Zoo" serves as a window to Victorian museum design.

The metal frame is all that's left of a wicker sculpture which once towered over the M5 motorway.

Legend says these rocks used to be hunting dogs, a story that may have inspired Sherlock Holmes' most famous case.

Old Tudor home moved on thick iron rails to a new spot.

These medieval tunnels provided water to the city above through centuries of civil war and plague.

Each year a new straw behemoth is born.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

The anatomical-pathological collection of a man who changed surgery.

This massive subterranean fissure is known as the "underground Grand Canyon."