The birthplace of Karl Marx is now a museum dedicated to the communist revolutionary's life and work.

Model Trains and Much More in Hamburg.

The 700-year-old fortress was the site of Count Orlok's castle in "Nosferatu."

A wunderkammer of exoticism immortalized by Tom Waits.

This contentious squat has stood through fire, violence, and government intervention as a hotbed of leftist protest.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

Thousands of flowers create enchanting pink tunnels over the city streets.

A radio telescope for listening to the stars, based in one of the cloudiest countries in the world.

This giant radio telescope would be a rusting ruin if it hadn't become such a beloved relic.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Moss and stone turn this waterfall into an otherworldly liquid veil.

There are thousands of tributes and memorials to the King, but none quite like this one in a Kraków city park.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.

The world's most delightful not-NOT-religion welcomes visitors to the town of Templin, just like its more stoic peers.

The largest toy museum in Poland showcases Europe's history of childhood.

Built during the Scottish boom in the oil industry, the village was never inhabited.

This ghost town in Belgium will lose its street art when it ceases to exist.

Villas that once served as playgrounds for the rich now fall away in decay.

This abandoned mining village was predicted to resist decay longer than any other modern human settlement.

You would never guess that before World War II this lonely field was a bustling German city.

This abandoned Belgian fortress is purposefully being left to nature.

A museum of alchemy and a basement laboratory all housed in an ancient building in a Gothic tower.

Underneath this small church are 15,000 bones, arranged by an obsessive academic.

Europe's second largest ossuary wasn't discovered until 2001.