Two stunning 17th-century libraries and a cabinet of curiosities.

Countless grotesque faces stare out from this eerie Prague art wall.

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

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

An eerie, existential museum dedicated to the author of "The Metamorphosis."

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

Humble beginnings for one of the world's most famous scientists.

Croatia's towering concrete blossom grows from the site of a World War II concentration camp.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

A tower marking the spot where Yugoslavia began its resistance against the invading Nazis stands neglected, but not quite forgotten.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

This huge metal monument is slowly being stripped to its concrete skeleton.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Structure built from the skulls of vanquished foes.

This symbol of Yugoslav liberation decorated with 620 carved heads of mythical creatures is now a forlorn relic of another time.

Curious carved stones and bird-like wings are a symbol of Serbian resilience and freedom on the site of a WWII massacre.

An abandoned monument remembering the "Pančevo Holocaust" now stands as a shadow of its former self.

Abstract monuments express sorrow and resilience at the site of a horrific massacre in Nazi-occupied Serbia.

A grand Yugoslav memorial to the group of partisans who fought and died resisting western Serbia’s Nazi occupation.

Serbia's master of striking memorials erected a forgotten, hidden gem in the hills outside a tiny village.

This memorial park stands on the site of one of the largest mass executions of the Second World War.

This spaceship-like Serbian monument reaches for the stars in celebration of the fallen fighters of fascism.

Destroyed Serbian army headquarters sits half crumbled in a largely revitalized Belgrade.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.