The tallest stationary dunes on Earth also happen to sing.

The coldest city in the world.

Stalin's prisoner-built rail line sits in ruin, never having a single car ride its tracks.

The world's second-largest excavated hole.

Stumps of an Ice Age forest, visible only at low tide.

The world's first and only escalator for lazy bicycles and their daunted riders.

Reclaimed by nature, the ruins of Doodletown, New York are remnants of a town consumed by a state park.

Shipwrecks, ruins, and turtles are all that remain on this haunting Caribbean ghost island.

Yugoslavia's biggest underground airport lies in ruins.

The largest ice cave in the world is thought to be the entrance to hell according to Austrian legend.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

This is not only one of the oldest collections in Europe, but also possibly the most beautiful.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

The world's most important buildings shrunk to a tiny size.

A small but immensely extravagant palace built by the "Night King."

The fairy tale castle of the "fairy-tale king."

Caves famous for the dragon-slaying saint who lived there.

The stones of this formerly witch-obsessed castle were used to build a church.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

The alpine falls where Sherlock Holmes apparently met his demise can actually be visited.

A whimsical bridge adorned with decorative dragons.

This one-time health resort was used by aristocrats around the world.

A historic observatory precariously perched at the "Top of Europe."