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

The curios of pharmacist and collector Henry Wellcome.

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

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

On October 17, 1814, a 15-ft. wave of beer ran rampant through the streets of London.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

On a wall in linear London, a plaque hangs at the high water mark of one of the worst floods in fictional Kcymaerxthaereal times.

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

This luxury shopping lane has been protected by its own tiny police force for over a century.

Claiming to be the oldest hat store in the world, this historic haberdashery had a hand (and a head) in the creation of the Bowler.

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

Pop culture has helped to keep this iconic British building from being destroyed.

London's old-school healing garden.

A clock designed to run with perfect accuracy for 10,000 years.

The sixth of London's "Magnificent Seven" cemeteries, and a source of unlikely inspiration to Beatrix Potter.

Public access to clean drinking water was an instant hit among the masses.

This one has sailed five times as far as Sir Francis Drake's famous ship.

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

A community of artists and entrepreneurs seeks a simpler life on London's waterways.

Scattered throughout London are ancient remnants of the city's former bounding wall.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This legendary stone is of unknown origin, and throughout history has been a literal touchstone for British leaders.

The site of London's first coffee house has been serving refreshments of one kind or another for 360 years.

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