Sweden's first nuclear reactor, R1, can be visited 25 meters underground.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

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

Pre-Nazi swastikas adorn the sculpted pachyderms flanking this brewhouse portal.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

Hans Christian Andersen for the postmodern world.

This sublime architectural marvel is a rare example of an expressionist church.

An ultra-modern diversity park in Denmark has turned an entire city block electric pink.

Copenhagen's celebrated theme park and gardens.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

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

A slice of central Asia in the middle of Berlin.

The fairy tale castle of the “fairy-tale king,” this was also the inspiration for Disney’s “Sleeping Beauty.”

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

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

Established in 1638 to battle the Black Death, this botanical garden is a treasure trove of rare flora.

Museum preserving torture methods from the past.

Cat art as far as the eye can see.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

A floating cat sanctuary on an Amsterdam canal.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

The world's only museum devoted to the wonders of fluorescence.