Rare karst landscape eroded from a flat seabed.

Skyscraper powered by wind turbines attached between its towers.

This statue once earned the distinction as one of the "Three Major Disappointments of the World."

Singapore's landscaping project is home to 18 incredible Supertrees.

This local emblem is the oldest and largest dragon tree in the Canary Islands.

According to the Guanches, the aboriginal people of the Canary Islands, the king of evil lives inside this volcano.

A Black Forest cuckoo clock theme park features one timepiece big enough to walk inside.

This medieval cathedral houses stained-glass windows featuring saints and pretzels.

These paved rills bring freshwater into Altstadt and could spell wedding bells for whoever stumbles into the waters.

Walk inside a half mile long crevice right outside the town of Garmisch Partenkirchen.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

A patchwork of ruins from various civilizations in one of the world's oldest continually inhabited cities.

An intimate look into the apartments of Jounieh via cable car.

This modernist cinema has survived war and reconstruction to become a symbol of Lebanon’s revolutionary spirit.

This building has survived for more than a century and remains virtually untouched.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

The world's longest and deepest train tunnel.

The bears of Bern have been a city highlight for over 500 years.

A once-thriving hotel in the Swiss Alps couldn't compete with climate change.

A breathtaking bridge that crosses a vast gorge over a river's torrents, and has a tale of a devil architect attached.

Apartment complexes built into huge repurposed natural gas tanks.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.