Time stands still at this serene burial ground in the center of Budapest.

A forgotten graveyard lost in the tangles of an overgrown garden.

This hidden art nouveau gem was designed by an architect in search of a national style.

Budapest's Communist-era statues, banished to the suburbs.

Once the home of a hermetic monk, this cave now houses a small church.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Its appearance in "Game of Thrones" may spur on the long-awaited restoration of this medieval shipyard.

A 16th-century Andalusian palace.

The world's largest wooden structure.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

This architectural oddity is an oasis of green on the outskirts of Valencia.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

This house's itty bitty size means no humans allowed.

This conical hill was built as a testing ground for an engineer known as the Glider King.

Super-heavy Nazi architectural experiment.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

Started as a kitchen garden, now the second largest botanical garden in the world.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.