A 16th century chapel decorated with bones, skulls, and entire bodies hanging from the wall.

An unusual "skull with ears" sits in the crypt of this small church tucked away at the end of a narrow alley.

Swarms of dainty flying insects swarm into the Petaloudes Valley to get busy.

An ode to a soldier who came to town, fell in love, then began making his own sparkling wine.

Launched by Napoleon's soldiers more than 200 years ago, a cannonball remains embedded in the tower wall.

A gothic church spire sits atop this skyscraper, the tallest church in the world.

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

Two stunning 17th-century libraries and a cabinet of curiosities.

Macabre astrological automaton clock dating to the late 1400s.

Statue of death tucked in the University of Medicine courtyard.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

These "anatomical machines" are only one of the many strange items in this Italian crypt.

This Parisian café sticks almost exclusively to an ethos of reuse.

Eighty million natural history specimens call this gargantuan museum home.

A unique bridge with an equally unique view.

This former Nazi castle was built as a school to train what would have been the future of the Third Reich.

An expansive book store, art gallery, and curio shop with wares ranging from tarot cards to novelty socks.

A beautifully eclectic mix of architectural styles.

The former home of a mad diplomat is said to still be marked in bloody, arcane scrawls.

A unique collection of gilded age mechanical pianos.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

This 22-floor tower's Skydeck offers panoramic views of Amsterdam.