The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.

This abandoned Belgian fortress is purposefully being left to nature.

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

A little sculpture with a large wardrobe.

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

Three floors of musical instruments coming from all corners of the world and hundreds of years of musical history.

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

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

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

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

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

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

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Macabre astrological automaton clock dating to the late 1400s.

An homage to the medieval rulers of Bulgaria.

A vast Communist-era exhibition space in the Bulgarian capital.

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

Said to be the only museum in the world dedicated to the most classic of all blooms, the rose.

"Holy Wisdom" overlooks the city that became its namesake.

Rock carving created 1,300 years ago 75 feet off the ground.

A striking symbol of the Bulgarian capital.

Mysterious standing stone formations looks like a petrified forest.

This ancient theater, restored in the 20th century, lives on as a venue for dramatic and musical performances.