Copenhagen's celebrated theme park and gardens.

A meow-velous tribute to a beloved street cat, made famous on the internet.

A Turkish monastery tucked into a cliff wall.

The deepest underground city in Turkey was designed to protect 20,000 people behind massive stone doors.

Hidden just under the waters around this Turkish island are the ruins of a once great city.

A Turkish ghost town abandoned in a population exchange with Greece.

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

Roman ruins top white travertine terraces formed by ancient hot springs.

This small town in the Netherlands has no roads but instead, miles of canals and over 100 bridges.

A little sculpture with a large wardrobe.

Climb inside an iron crystal magnified 165 billion times its normal size.

A beer pipeline runs beneath Bruges.

This gruesome biblical parade celebrates the one day a year that a bit of Jesus' blood turns to liquid.

Christ's blood preserved in a Belgian town.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Five candy-colored villages on the Italian Riviera.

This community on a small Venetian island has taken to painting their houses in bright neon hues.

A copy of the famous statue can be found in this Florence piazza, along with one of the most breathtaking views of the city below.

Secret refuge and museum of the Duke of Florence.

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.