Throughout this shopping mall are medieval ruins that were discovered during the mall's construction.

The last municipal pneumatic post system in the world was in operation for over 100 years, and may run again.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Street artists transformed an abandoned air vent into the beloved Star Wars robot.

This artificial cave looks like something out of a fairytale.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

Looming communist pillar with a Czech twist.

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.

One of the first canal boat-lift inclines ever created.

Austrian and Germans who died on British soil during World War I and II are buried here.

Parts of this former military training ground may have inspired parts of J.R.R. Tolkien's famous fantasy series.

Lavish royal estate punctuated with heated greenhouses.

The Belgian royal family's private depot now stands abandoned and forgotten alongside the tracks.

A huge old mansion full of thousands of toys, each there to be used and played with.

This enormous steel tube is the biggest speaking horn in the world.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Intricate metal sculpture that's half gothic cathedral, half construction equipment.

This modern arts center is built around a gem of late-Baroque architecture.

A bronze statue of the fictional character nicknamed "Mrs. Hat" from a beloved Belgian comedy.

Belgium’s famous peeing statue has worn many hats (and coats, and pants), which are on display at this small museum.

When you're a great Russian Tsar, even your vomit gets a statue.

Two geological phenomena in one precarious locale: a towering stone window, and a deep blue void.

This church is named for one of the most dramatic tales in the early Christian church.

These temples are among the oldest free-standing stone buildings in the world.