The Pope’s secret escape route.

This enormous monument is one of the most iconic structures in Tokyo, rudely nicknamed "The Golden Turd."

An enormous pair of straw sandals woven in the traditional way—to keep demons at bay.

After being lost for decades, this striking mural depicting the atomic bomb covers the wall of a busy Tokyo metro station.

Once a black market electronics marketplace, now an otaku shopper's paradise.

After a profound show of devotion for his master, a dog becomes the symbol of loyalty for an entire nation.

Not quite the menace it once was, this monster still has some chops.

This Buddhist temple is home to the graves of the Japanese national legends, the 47 Ronin.

A 20-meter (65-foot) robot towers over Tokyo Bay.

A Japanese concept restaurant that feels like a party thrown by the monsters in your closet.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

A floating cat sanctuary on an Amsterdam canal.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

Locals say the stone that marks the spot where the gallows once stood can lead you astray.

The ruins of this Dutch castle sit atop a labyrinth of once-secret tunnels and passageways, dating back over 900 years.

A Belgian self-built tower inspired by the Bible and ancient civilizations.

This sprawling Belgian fort was once thought of as impenetrable but now it is simply an abandoned relic.

Incredible labyrinth of man made caves.

This historical Netherlands fortress still bears the marks of its single siege.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

Be(w)ar(e) the moat around this historic Czech castle.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.

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.”