It was once nicknamed "the most bombed hotel in Europe."

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

This pedestrian walkway cuts through a cemetery and over several burial vaults.

There was a top secret plan during World War II to seal a group of soldiers inside the rock.

Local legend says Isaac Newton built this footbridge without any screws, bolts, or nails.

The most loyal of little dogs, or a Victorian era publicity stunt?

Protecting the dead from opportunistic body snatchers.

A sweet symbol marks the place where torturous executions were once carried out.

This short bridge is the only thing connecting a tiny Irish island to the mainland.

The Metropolitan Police refurbished the blue box (perhaps not coincidentally) the same year "Doctor Who" returned to TV screens.

London's smallest police station is barely the size of a phone booth.

Catacombs turned marketplace.

Northern Ireland's Brobdingnagian stepping stones.

The atmospheric road was never meant to be so creepy.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

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

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

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

Birthplace of the Tendai sect and home to the marathon monks.

The name of this tiny pocket park tucked between two buildings on Manhattan's Upper West Side is Latin for its location: "seventy-one."

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

Elevated freight railway turned wildly successful urban park.

A terrific purveyor of natural history objects and curios.