This snug medieval lane is one of the narrowest streets in the world.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.

Romania's triumphal arch looks out over Bucharest.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

A celebration of all things tacky, garish, and bizarrely creative in the Romanian capital.

This Prague museum collects brutalist relics and memories from the country's former Soviet rule.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Bridge that died in war and was resurected.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

This historic cemetery was inaccessible for several years due to dozens of land mines.

The place where World War I began.

Oriental bazaar in the heart of Sarajevo.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

The first mosque in the world to receive electricity.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

A collection of art from Bulgaria's time as a communist state.

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

A striking symbol of the Bulgarian capital.

Eastern Bloc nostalgia, anybody?

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

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

A miniature train-ride through Slovenia's largest cave system.

A whimsical bridge adorned with decorative dragons.

When this monument to Slovenia's national poet was erected, it's said to have sparked the ire of nearby church authorities.