This small museum in a former church crypt contains artifacts of the Elephant Man, Jack the Ripper and Florence Nightingale.

A network of concealed passageways lies within a busy London Underground station.

A Victorian natural history and ethnographic museum with wonderful turn-of-the-century, science-book-esque evolution displays.

A 2000-year-old Roman amphitheater lies just below Guildhall Yard.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

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

A historic London pub with prison cells in the cellar and a "spy room" on the second floor.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

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

The anatomical-pathological collection of a man who changed surgery.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

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

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

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.

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

Brooklyn's most iconic restaurant, resurrected.

An everyday Jackson Heights bodega conceals a Mexican seafood paradise.

This castle-like building in Manhattan helped destigmatize cancer in the 19th century.

“Wagon Jobber" turned smokehouse magnate's family-owned business is still going strong 100 years later.

Spike Lee's provocative film is officially honored right where it was made, the first time a work of art was used as a secondary street name.

Where the four original members of the Ramones hung out and revolutionized punk rock.