One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

Inspired by Thomas Stothard's painting of the "Journey to Canterbury," albeit with Canterbury natives.

It is said the legendary wizard once lived in this sea cave beneath Tintagel Castle.

The oldest working mechanical clock in the world.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

This coffee shop lies hidden beneath a historic church.

These Victorian era devil sculptures were designed to spite a local vicar.

Rebuilt remains of a temple to Roman god Mithras.

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

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the first ‘Harry Potter’ film.

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

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

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

This railroad and oil tycoon's lavish estate now stands as a time capsule of the Gilded Age.

This nondescript tunnel has been featured in a number of iconic movies, from “Roger Rabbit” to “Back to the Future.”

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

This church houses the “incorrupt” body of its founding Bishop.

Every weekend, the parking lot of this Buddhist temple turns into a Thai street-food paradise.

Hidden above a drug store on a nondescript corner of Lincoln Heights is a private clubhouse for intrepid explorers.

Resting place of Hollywood's immortals is also site of summer film screenings.