Known as the "Dodo Manège," this carousel features a herd of animals that have disappeared—or may be gone soon.

Behind the pink curtain, Au Bonheur du Jour, an art gallery of erotic archives.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

A museum of magic with a Sadist past.

A haunting collection of the vanished and disappearing natural world.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

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

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

This massive library holds what was once the largest book collection in the world.

The oldest stone house in Paris was built by its most famous alchemist.

France's most famous cemetery, with some of its most curious tombs.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

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

Ireland's only German military cemetery holds the remains of a spy who was moved there under the cover of darkness.

A retired military stronghold on the rolling green coast of Donegal.

An ancient holy well said to be used by the patron saint of sailors and travelers, lost in the boggy west of Valentia Island.

An important landmark in the history of algebraic logic.

The ruins of an 800-year-old monastery boasts the tallest round tower in Ireland.

An 80-year-old plane tree is devouring an iron bench at Ireland's oldest law school.

Just a few miles off the western coast of Ireland lies an isle steeped in Irish literary history.

This 30-foot pile of rocks may be the grave of a mythological Irish queen.

After being destroyed by IRA sympathizers, the ruins of this stately Irish manor have sat vacant for decades.