Long-abandoned trolley tunnels just a mile away from the White House are turning into an art space.

Colorado's only true geyser is hidden within the San Juan National Forest.

This replica stave church looks like a piece of Norway was simply plopped down in South Dakota.

The ancient sauropod tracks found in this former quarry are some of the largest in the world.

Iceland's first pagan temple in 1,000 years is underway in Reykjavík.

This stunning concert hall has become a symbol of Iceland's national recovery.

This black church sits alone among a field of lava rock.

Every summer local children form "pysja patrols" to save young birds that have wandered from their nests.

This natural Icelandic fissure allows divers to swim right between two volatile tectonic plates.

One of the deepest indoor swimming pools in the world.

These slanted cubic abodes are a creative if odd solution to a zoning pickle.

Drive past the giant fruit sculptures and up to the window for a menu of fruity treats.

This medieval castle was painted pink as part of a now-abandoned children's theme park.

This neighborhood of futuristic ball houses looks like an alien settlement in a science fiction film.

Colorful and chaotic stacked hotel in North Holland.

Europe's first floating restaurant is home to a hilarious legend.

To enter this cluttered-yet-cozy sanctum of Belgian brews, ring the bell and tell the gatekeepers you've come “to taste beer.”

This recently restored crypt was once plagued by liquefying coffins and exploding caskets.

Head underground and take a tour of the city's working sewer system, and see the underground river Senne, which defined Brussels for centuries before being covered in the 19th century.

An open-air sewer system that was covered piece-by-piece over 300 years.

Take a leisurely walk through the park to find the seven giant troll sculptures hidden throughout the park.

Climb inside an iron crystal magnified 165 billion times its normal size.

The subtle science of a master molecular gastronomist.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.