A tribute shrine where the Space Invasion street art movement started.

The storefront of a ramshackle Parisian puppet theater.

This mural painted by Keith Haring was done without payment as a gift to entertain the children at the Hôpital Necker.

What looks like a normal building is really a hollow facade hiding a subway vent.

A magical, macabre wax museum, beloved by locals, uses real artifacts to depict an assassination from the French Revolution.

This Paris art space celebrates the creativity and ingenuity that springs from abject poverty, especially in Africa.

A unrivaled and rather horrifying collection of wax dermatological models.

An off-the-beaten-path boutique stuffed with an eclectic collection of upcycled goods.

Paris' fabled purveyor of exotic taxidermy and natural history curios.

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

Statue of death tucked in the University of Medicine courtyard.

A museum on the history of Paris, including a set of Napoleon's toiletries, Proust's room, and relics of the Revolution.

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.

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

A museum of carnival attractions where you are invited to ride the rides.

On a small Slovenian island, diners can mix and match a classic cake into dozens of sweet and savory flavor combinations.

An ancient tree that was once the favorite of a young Swedish royal.

Located in an old church, this brewery produces a different kind of holy water.

Street artists transformed this abandoned industrial neighborhood into one of Europe's largest graffiti exhibitions.

The historic tower houses of this nearly abandoned Greek town have been compared to the spikes on an iguana's back.

Inscribed on the gate are the names of 29 figures from the University's first five centuries.

One of the most spectacular bridges in Spain spans a narrow chasm that divides the city of Ronda.