Montmartre's sole surviving windmill became an iconic landmark for 19th-century painters, artists, and bohemians.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

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

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

This 18th-century sundial was designed to calculate the date of Easter each year.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

The celebrated eyesore created by starry-eyed sweethearts.

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

Notorious artist squat renovated into legal studios.

This modest marker near Notre Dame identifies the very center of Paris.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

After a nearly successful attempt on Hitler's life, the conspirators met their fate in the courtyard of this Berlin building.

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.

The bunker where Hitler took his own life is hidden under this deliberately ordinary parking lot.

Cold war icon and onetime "hole" in the iron curtain.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

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

This chimerical bridge/tunnel appears to dead end right into the sea.

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

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

Opulence and fantasy collide in this royal chair which is supposedly made with unicorn horns.

The old observatory in Copenhagen has a spiral corridor used as a racetrack.

Copenhagen's celebrated theme park and gardens.