There was a top secret plan during World War II to seal a group of soldiers inside the rock.

The architect of this fanciful complex called it an "oasis for humanity and nature in a sea of rational houses."

A six-story, asymmetrical tower filled to the brim with scientific experiments.

If you visit the burial place of King Frederick the Great, you'll likely find a couple of potatoes sitting on his tombstone.

The "Prussian Versailles" that is as glorious today as when it was built.

A quaint Russian village in the middle of a German metropolis.

Germany's Glienicke Bridge has a shady history of clandestine meetings, espionage, and spycraft.

This sculpture in Denmark presents Arnold Schwarzenegger embracing his own doppelgänger.

This colorful artistic feature atop a Danish art gallery allows visitors to stroll through a rainbow.

Long before the hollyhocks and colorful facades, this lane was notorious for witch trials, infanticide, and prostitution.

A symbol for the opposition to nuclear power around the world.

The final home of the legendary Danish sailor said to have lived to be 146 years old.

At these downtown crossings, pedestrian lights show axe-wielding Vikings instead of the usual walking figures.

A massive bell inside a Danish library rings to announce the birth of a baby in the city.

This inverted metropolis model is the artist's "revenge" for not being allowed to have a doll house as a kid.

This ordinary street was made infamous by a legendary visit from the devil.

Beneath Denmark's Højbro bridge, a bronze merman and his seven sons forever mourn for the mother and wife who left them for land.

Denmark’s ultra-modern library hides a treasury of rare, unique books.

This bridge's unique architecture honors nautical heritage and encourages self-awareness.

Copenhagen's "other" little mermaid marks the historic location of past sea maid sightings.

This contemplative sculpture made out of old machine parts is meant to be the first in a series of sculptures around the world.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

Stockholm's tiniest statue is of a small boy looking at the Moon.

A 130-year-old urinal is the oldest of Stockholm and perhaps all of Sweden.