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

Originally built for London’s cab drivers, this bright green hut now serves anyone a hot drink or meal.

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

Protecting the dead from opportunistic body snatchers.

These steps offer a breathtaking view of one of Europe's most besieged fortresses.

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

This otherwise ordinary close on the Royal Mile constituted the end of the world for Edinburgh’s poorest residents.

A statue in the heart of Edinburgh honors a bear that served in the Polish military during World War II.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

This obscure walkway links Edinburgh’s Old Town with one of the city's prime vantage points.

The television series' iconic giant foot was borrowed from this classical painting.

A 18th century graveyard and its astonishing cortege of macabre iconography.

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.

This 17th-century street hidden beneath Edinburgh was once a breeding ground for the black death.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

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

The pockmarks across the building's facade are remnants of the Blitz.

A statue of the legendary Celtic warrior queen who fought the Roman invaders stands in one of the cities she once destroyed.

The cedar tree in Highgate Cemetery earned its title by accident.

A naturally mummified 2,000-year-old man.

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

After nearly 60 years, there's still a bear at Paddington Station looking for help.

Eighty million natural history specimens call this gargantuan museum home.