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

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

France's national museum of scientific and industrial instruments.

A surrealist timepiece by the artist of melting clocks.

A museum of magic with a Sadist past.

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

A mechanized clock where a man fights off a dragon, crab, and rooster.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

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

One of the oldest medical collections in Europe focusing on rare surgical instruments.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

Paris' linguistic guide to the international language of, yes, love.

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

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

Abandoned railway line circling the city of Paris.

Notorious artist squat renovated into legal studios.

An unassuming historical marker for an iron age fort leads you to an oddly adorned cemetery for unbaptized children.

These moss-covered medieval ruins tower atop the smallest of Ireland's Aran Islands.

An oddly conical beacon perched atop beautiful Irish cliffs.

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

A mysterious Neolithic tomb is perched along the edge of a modern golf course.

The ruins of a medieval monastery named after a type of tree.

This Bronze Age tomb is the centerpiece of a clearing within a beautiful Irish forest.

A stone wall that mysteriously moved three feet from its foundation.