Once one of the largest rooms full of books in the world, this bookstore basement is still a treat for bibliophiles.

Once the central jail for Los Angeles, this building housed inmates like Al Capone, those arrested from the Zoot Suit and Watts Riots, and individuals imprisoned for their sexuality.

The decor of this Hollywood movie palace just barely predated the opening of King Tut's tomb.

This peaceful garden is hidden on the grounds of a spiritual organization founded by a pioneer yogi.

An iconic location along the Los Angeles River where countless movie scenes are filmed.

The neighborhood of Eagle Rock is named after a gigantic boulder with a shadowy surprise.

This intriguing Bronze Age artifact spent centuries hidden within a Welsh faerie hill.

A giant scrawl on the skyline of south London.

The medieval woodcut-style artwork chronicles life in medieval London.

The commemorative stone column conceals a secret laboratory.

Since 1887, this old-school shop has stacked its shelves with extraordinary coffees and teas.

The bronze uniforms commemorate the vital role of women during World War II.

The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

This once-controversial and slightly confusing statue of Achilles was built out of captured cannons.

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

Chelsea's soldiers were given strict orders when crossing this historic bridge.

Preserved behind glass, the ruins of a medieval building used to store human remains.

A masterpiece of Art Deco architecture hidden in plain sight in West London.

At the top of the hour, figures of the London department store's two co-founders emerge and bow to each other.

You can still see bits of the camouflage used to hide this Art Deco building from bombers during World War II.

The arching stretch of London's longest street holds many reminders of the area's maritime past.

Down a pint of ale where the Bishop of Ely's servants slept in 1546.

Once designed as the entrance to Buckingham Palace, this structure was later relocated and stands as a victory arch.

Order a salt beef-loaded beigel at any hour of the day or night at this East End institution.