The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

Dublin's most modern, visually spectacular bridge is modeled after Ireland's national emblem.

This neon landmark has been posing this deadpan question to follicly-challenged Dubliners for over 50 years.

The modern birthplace of Irish freedom.

The enchanting archway is the only surviving portal into Dublin’s lost medieval wall.

Uh, pardon me, ma'am, but I couldn't help noticing that there's a Columbo statue in the middle of Budapest.

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

A 12th-century fortress containing some of Berlin's oldest buildings.

The oldest museum in Russia is home to a fascinating collection of nearly two million anthropological artifacts and anatomical curiosities.

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

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

A pair of mosaics marks the spot where the last accused witch of Dundee was put to death.

People leave coins atop an unusual grave marker in one of Scotland's oldest burial grounds.

Nestled amid the peaks and lochs of the Scottish Highlands, this inn and pub has played host to outlaws and ghosts.

These ruins witnessed the final gathering of the failed Jacobite Rebellion.

The most loyal of little dogs, or a Victorian era publicity stunt?

A scattered trail of street art adds a pop of color to the city's stark structures.

This castle was established by the 4th Duke of Montrose and is connected to the Buchanan Clan.

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

One of the most poignant ruins of the Chornobyl nuclear disaster, the local football team's stadium has been quickly reclaimed by nature.

This attraction was abandoned after the Chornobyl disaster.

The ghost town left by the worst nuclear disaster of all time is being taken over by nature and urban explorers.