Rebuilt remains of a temple to Roman god Mithras.

London's amazing modernist public square that never was.

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

The last four extravagant street signs of London's historic banking street.

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

The 2,000-year-old beam is tucked within the pedestrian entrance to the old London Bridge.

The Great Fire of London and the regulation of one-way streets both started in this alley.

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

A Roman spa buried deep beneath the City of London.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

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

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

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

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

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

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

The barrel-made lookout from Shackleton's final ship is tucked away in the crypt of one of London's oldest churches.

An architectural oddity hides in plain sight on this iconic London bridge.

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

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

The remains of an ancient Roman teenager are memorialized at the base of a modern London landmark.

This unassuming building produced some of the world's most famous bells.