From Nazi chemicals to the CIA, this architectural marvel has played a fascinating role in German history.

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

An ossuary built in 1210 to collect bones from the Ospedale Maggiore of Milan.

The secret medieval communication system will whisk your words above the noise of the crowd.

Before there were doorbells this bronze ear was installed for visitors to announce their arrival.

This giant middle finger statue sends an unambiguous message to Italy's bankers.

This poignant art installation raises awareness of violence against women.

Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

The last bastion of Roman presence north of the Alps looms over a German town.

The Goose Girl of Göttingen, Germany might well be the most kissed girl in the world.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

A beer pipeline runs beneath Bruges.

The compass on its front was a handy tool for 17th-century merchants who needed to know the direction of the wind.

Potato-peeling mannequins, Inca art, and a dangling tuber mobile help trace the history of fries at this Belgian museum.

The body of at least one victim of a construction accident was left behind in the collapsed pylon, buried under tons of concrete.

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

Thousands of tourists and residents in Cologne affix "love padlocks" on the Hohenzollernbrücke Bridge to symbolize their affections.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

A monument to the three wars that led to German unification towers within a Berlin traffic circle.

Cold war icon and onetime "hole" in the iron curtain.

A restaurant and observation deck built in a unique broadcasting antenna.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".