An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

This virtually windowless mass of smooth concrete is the only Catholic church in the city.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

A forgotten remnant of the Soviet Union, Transnistria is an unrecognized country hidden behind a heavily militarized border between Moldova and Ukraine.

This massive monument was unveiled the day Kosovo declared independence from Serbia.

A 11-foot former president stands on a Kosovo street that also bears his name.

A futuristic, brutalist masterpiece that is also strangely prison-like.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

The Adriatic's most famous wind can be reliably experienced in the city's Marina.

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

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

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

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

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

A crushed gate and giant bronze head serve as a reminder of Greece's fight for freedom.

Where commuters walk through remnants of an ancient Greek necropolis.

Legend says this sacred tree was a gift from goddess Athena.

The Cycladic architecture makes this Athens neighborhood feel like an island paradise hidden in the shadow of the Acropolis.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A church of bones, decorated with 40,000 human skeletons.

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

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.