The key to turning shifting dunes into the green oasis of Golden Gate Park.

A collection of memorabilia from the Beat era in the back of a San Francisco bookstore.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

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

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

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

The remains of the great moral philosopher reside in a university in London.

An unusual round church in London with a Templar past.

A cluttered and astounding collection of antiquities and curiosities.

A surreal statue honoring Prague's favorite literary son.

Looming communist pillar with a Czech twist.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Two stunning 17th-century libraries and a cabinet of curiosities.

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

Elevated freight railway turned wildly successful urban park.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A magical place that lets you play in and explore the world of Studio Ghibli.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.