This overlooked street light once served as a KGB dead letter box.

The bar where "The Great Train Robbery" was planned was once a nexus of high society and low morals.

A special shop catering to the needs of things that go bump in the night, and also helps kids become writers.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A tongue-in-cheek arcade where the games are based on everyday life.

Three-story slide through the New Museum.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

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

This 1920s Dutch barge is now a floating bookstore.

A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

Drink your espresso at a Victorian-era urinal in this underground-restroom-turned-coffee-bar.

More than a million titles fill the labyrinthine shelves of this prestigious private library.

This luxury shopping lane has been protected by its own tiny police force for over a century.

The next-door homes of two very different musicians, George Frideric Handel and Jimi Hendrix.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

This museum inside a museum tells the story of London's timepieces.

Repository for more than 22 million pickled specimens.

A glorious pub known for a spiteful printing feud and its famous typeface lost—then found—at the bottom of the Thames.

Floating pink tap installed for a flower show in London.

A collection of machines designed to break things for science.

In 2013, historians discovered a hidden room devoted to the art of making royals' hot chocolate.