This innovative steam machine was no doubt the most famous of the pioneer locomotives.

A relic of Victorian grandeur hides beneath a busy South London road.

A labyrinth hides in plain sight at each of the city's 270 Tube stations.

The taxidermied remains of a once-great parrot.

The majority of the museum's large collection is held in a storage space open to the public a few times a year.

A quiet memorial to those who died saving others in the heart of the City of London.

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

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

Art Deco and “Wrenaissance” mash-up, this recently restored royal residence has been home to kings and comes with secret monkey passages included.

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

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

A network of concealed passageways lies within a busy London Underground station.

Abstract dinosaur models in London.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

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

The remains of Crystal Palace Great Exhibition of 1851.

A historic London pub with prison cells in the cellar and a "spy room" on the second floor.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

Hear the quietest sound from across the dome.

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

A student driver's nightmare.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

This South London cemetery holds the remains of more than 15,000 people.