This unique architectural wonder is home to luxury apartments.

The northernmost point in Denmark is a turbulent sandbar created by two clashing seas.

The world's largest maze is a nature park with nearly 200 decision points.

Nearly 40 miles and 1,000 years of limestone mines under Denmark.

A natural wonder in south Denmark.

Old Danish castle immortalized in Shakespeare's Hamlet.

This sublime architectural marvel is a rare example of an expressionist church.

A 19th-century subterranean reservoir repurposed as a contemporary art cave.

Copenhagen's celebrated theme park and gardens.

This 14th century castle withstood years of battle but is now sliding off the hills into the Danube.

A sinuous path among steep cliffs creates a stunning sight in southwestern Serbia.

Legends of treasure and spirits flow from this this fairy tale-like oasis.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

Budapest's Communist-era statues, banished to the suburbs.

At almost 900 feet long, this is Bulgaria's longest suspension bridge and the only way to reach the small village of Lisitsite.

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

An abandoned saucer-shaped monument in the Bulgarian mountains.

An architectural marvel that spans the Arda River, and has stories of a haunted past.

Locals believe this abandoned ruin on the outskirts of Bucharest is haunted.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

A dilapidated amusement park with a million-dollar view.

This bridge is so steep it looks like a rollercoaster.

The 43-mile route crosses through six islands with gorgeous views of the Seto Inland Sea.

On Japan's Tashirojima Island, cats are king.