Inside a humble hangar is some of the best roller derby the world has to offer.

Though its celestial ceiling is impressive, the true star is the vast collection of French books.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

Catacombs turned marketplace.

This tangled English forest looks like something right out of a fairytale.

A fantastic castle rumored to be the birthplace of King Arthur.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

The world's largest collection of witchcraft regalia.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

A charming flea market shop dedicated to retrofuturistic apparati.

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

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

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

This 1920s Dutch barge is now a floating bookstore.

A historic house left in "dramatic still life."

Rebuilt remains of a temple to Roman god Mithras.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.