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

This former medical factory gives home to cutting edge arts in the shadow of a gas works.

The Columbia Road Flower Market is now open every Sunday, rain or shine.

A recently restored Shoreditch landmark with ties to Jack the Ripper.

Artists and musicians now rule over this former rail station.

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

This pump on the bad side of Victorian London betrayed a horrifying revelation about the water supply.

Eighty million natural history specimens call this gargantuan museum home.

A hidden treasure in London with a rich medieval history, and the resting place of many luminaries.

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

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

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

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

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

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

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

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

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

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

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

The curios of pharmacist and collector Henry Wellcome.

A hands-off space for graffiti artists to hone and display their skills.

An unusual round church in London with a Templar past.

The anatomical-pathological collection of a man who changed surgery.