The celebrated eyesore created by starry-eyed sweethearts.

A 400-year-old church covered floor to ceiling in ex-voto offerings from the faithful.

This bridge was constructed from the rubble of the infamous Bastille.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

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

Paris' linguistic guide to the international language of, yes, love.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

This 15th-century island fortress later served as home to the executioners no one wanted to live near.

The hallucinogenic center of the ancient world.

Ancient serpentine sacrifice holder that has stood the test of time.

This remarkably well-preserved Egyptian plinth is pretty well traveled for a giant piece of stone.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

A marvel of Byzantine engineering under the streets of Istanbul.

A fearsome dragon clings to a corner of Munich's city hall.

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

The footprint of a frustrated devil in Munich's Cathedral.

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

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A Christian monastery stands on what was once a holy Incan temple.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

An Inca spa, military outpost or maybe… both?