A memorial for public executions that dates back to the 14th century.

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

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

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

The ritual has been performed uninterrupted for nearly 700 years.

A mysterious suspended hand greets unsuspecting visitors at the Tower of London.

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

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

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

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

There's an exclusive Beefeaters pub hidden in the Tower of London.

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

The last remaining example of the boatmen's perches that once dotted the south bank of the Thames.

The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

A living memorial to the trees London lost during the Great Storm of 1987.

An unusual ode to the late Irish playwright, complete with a squiggly bust and coffin-shaped bench.

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

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

Originally meant to hold a statue of King William IV, this support sat empty for years. Today, it hosts a rotating cast of public artwork.

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

This ancient Egyptian obelisk still bears the wounds of World War I.

The broken skateboards that became a poignant memorial to a murdered skater.

A haunting monument dedicated to the Royal Naval Air Service and the Fleet Air Arm.

The bronze uniforms commemorate the vital role of women during World War II.