Old Danish castle immortalized in Shakespeare's Hamlet.

An eerie, derelict amusement park in Berlin.

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

An old department store turned Nazi prison turned artist commune.

The most visited, and possibly most controversial, museum in Germany.

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

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

Copenhagen's celebrated theme park and gardens.

A museum of carnival attractions where you are invited to ride the rides.

The headless bodies of more than 1,300 guillotined victims of the Reign of Terror are buried here in mass graves.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

Egyptian Revival movie palace abandoned for decades and restored in 2013.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

Stroll through retro Paris while shopping for old postcards and discarded doll heads.

Vortex-shaped aquarium hosts Europe's largest school of piranhas and other ocean creatures.

Weird wax anatomical models reside here, as do other anatomical specimens.

19th century pendulum and a clock restored by a rogue group of guerilla artists.

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

Walk upon the mementos of the dead in this Parisian courtyard paved with medieval tombstones.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Notorious artist squat renovated into legal studios.