A student driver's nightmare.

A subterranean ice warehouse that has lain hidden beneath central London for over a century is now open to the public.

Banksy gives themself artistic license with this piece of London street art.

One part local history, 99 parts gruesome haunted house.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

A kaleidoscopic warehouse-maze of handmade neon signs.

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.

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

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

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

The place to be if you love vintage Swedish cars.

A former hen house turned curiosity cabinet displays one man's lifelong fascination with cannibalism.

Now a hotel, this former bank was the site of a robbery that spawned a psychological phenomenon.

This Stockholm light tower can be controlled by anyone with a smartphone.

The library's graceful rotunda is like a bibliophile's temple.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

From Coke II to Google Glass, this exhibit features some of the most spectacular commercial flops.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

What happens here stays here – unless it affects the whole world.

The "Seinfeld" diner.

One of the few remaining American elm trees in New York’s Tompkins Square Park was the birthplace of a new religion.