The world's most famous cheese caves.

Half a century after it was abandoned, this ghost town is coming back to life.

The world's tallest bridge is also possibly the most elegant.

There is a strange little carving of a person seemingly crushed by a pillar behind the remains of St. Thomas Aquinas.

This watchtower once presided over the Berlin Wall.

An "evil painter" included pointed symbols in this artwork to poke fun at members of the Danish Parliament.

This pair of gilded girls atop an Art Deco building in Copenhagen were built to function as a weather indicator.

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

Climb to the top of its spiral spire for spectacular views of Copenhagen.

A little-known cafe in an old copper bridge tower with 360-degree views of the harbor.

A Victorian park cemetery, standing on the site of what was once the Great North Wood.

This pub was 238 years old when it decided to revamp its image: It started serving Thai food.

A labyrinthine network of chambers with a storied past hides below Edinburgh's South Bridge.

This abandoned Belgian fortress is purposefully being left to nature.

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

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

Incredible labyrinth of man made caves.

This former steel and coal plant is now a neon-lit industrial fantasia.

The world's biggest pet store.

No need to strap in for a "ride" on this walkable roller coaster.

It's possible to walk inside one of the largest Neolithic tombs in Britain.

The largest stone circle in the world has ended up bringing up more questions than it has answered.

A Victorian marvel of engineering is now a 21st-century tourist attraction.

The majority of the museum's large collection is held in a storage space open to the public a few times a year.