One of the few places of its kind, this space research center sits deep in the countryside of Matera.

An abandoned shopping gallery built during Fascist Italy tucked in the center of Palermo.

A study of Fascist era Art Deco design in Italy.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.

On the wall of this medieval walkway, a symbol of the Spanish Inquisition.

The unexpectedly beloved remnants of a controversial thermal power plant.

This home designed for chocolate magnate Antoni Amatller is an exquisite treasure-box of Catalan Modernism.

For one day every month Barcelona's Estació de França transforms into a market for model trains.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

Barcelona's historic 19th-century sewers, whose foundations were laid in medieval times, are open to the public for exploring.

This abandoned oil depot produces world's longest echo in a manmade structure.

On a site with a long military history, a 1980s shelter.

This obscure walkway links Edinburgh’s Old Town with one of the city's prime vantage points.

The taxidermy remains of the first mammal ever cloned from an adult cell are on display in Edinburgh.

A book bound in the skin of an infamous criminal, along with countless other specimens.

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

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

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

A church of bones, decorated with 40,000 human skeletons.

The final resting place of the great navigator, or maybe his brother.

Europe's simulation of the Martian surface uses soil from Mount Vesuvius.

Now an entertainment complex, the Lingotto building was once an avant-garde auto factory with a test track on the roof.

The astonishing collection of an infamous criminologist.

The final resting place of the famous violinist, after his corpse was denied a proper Catholic burial for decades.