Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

An existential riddle in the world's largest ancient castle.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

Macabre astrological automaton clock dating to the late 1400s.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.

This doorless 20th-century elevator doesn't stop or slow down.

A Jenga-style cylindrical tower of books that appears to go on forever.

This walkway is so narrow it needs its own light to stop pedestrian traffic jams.

This automated sculpture of two men peeing will spell out text messages with their micturition.

A plaque marks the spot where the saint was shoved off the Charles Bridge and into the river.

A grumpy old water goblin guarding an old mill on the Devil’s Stream in Prague.

A series of playful yellow penguins share a serious message about the environment.

The medieval "Bearded Man" relief still serves as a clever flood warning marker.

The hidden lair of an alchemist rediscovered in a 2002 flood.

A surreal statue honoring Prague's favorite literary son.

One of the famous Czech artist's lesser-known Prague installations appears to be a glowing fetus affixed to a drainpipe.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

Avoid gangster interaction while window-shopping.

The Bloemen Route, or “Flower Route”, stretches 25 miles through prime Dutch tulip country as a result of “tulip mania,” the world’s first economic bubble.

The beloved beast's taxidermy remains sit in the Natural History Museum's cafe.

This marine reptile was discovered by one of the 19th century's greatest fossil hunters.

The famous polar explorer stands outside the Royal Geographical Society's headquarters.

The pockmarks across the building's facade are remnants of the Blitz.

Revel in the Victorian splendor of the world's oldest eating establishment inside a museum.