The quirky - and private - constructions of a secluded artist depict the house of God.

An ancient woodland that inspired a young J.R.R. Tolkien.

Green labyrinth formed by a karstic maze hidden in a preserved oak forest.

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

Home to 10,000 medical specimens including the remains of Rudolf Virchow's extensive collection of pathological specimens.

At one of Berlin’s oldest churches, visitors can place mosaic tiles to help restore a medieval mural.

A popular shrine where the Blessed Virgin allegedly appeared in 1830, displaying a holy armchair and two incorruptible remains of Lady Saints.

The recovered bones of martyrs slaughtered during The Terror are on display in this church crypt.

A unrivaled and rather horrifying collection of wax dermatological models.

A grotto-like lodge decorated with gilded mosaics, rocks and a noisy waterfall was the setting for the most sumptuous pleasure house of 1900s Europe.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

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

Statue of death tucked in the University of Medicine courtyard.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

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

A surrealist timepiece by the artist of melting clocks.

France's national museum of scientific and industrial instruments.

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

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

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

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

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

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