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

The rose garden in Regent's Park where Pongo and Perdita met for the first time in Disney's "101 Dalmatians."

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

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

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

This otherwise ordinary close on the Royal Mile constituted the end of the world for Edinburgh’s poorest residents.

A museum wholly devoted to juvenescence.

One of Europe's oldest libraries.

Ship-sized kinetic sculptural fantasy.

Installed at a chaotic intersection, this gave London traffic cops a place to hang their heavy woolen coats.

Climb this overlooked gem's spiral staircase and you'll be rewarded with spectacular views of Glasgow.

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

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

Once a train station along the Great Eastern Railway this vibrant coffee shop and bar is where members of London’s creative class mingle.

An English artist has turned an unassuming ex-council house into a time-lost house of mystery.

Lovers proclaim their unbreakable bond by leaving their names on locks fastened onto the Shoreditch fence in East London.

The first tunnel to be dug beneath a river, repurposed as an art and museum space.

This allegedly haunted 16th-century tower house-turned-museum exhibits thousands of spectacular objects.

The final resting place of soldiers' loyal canine companions.

A sweet symbol marks the place where torturous executions were once carried out.

An abandoned tank sits in an empty London lot as a symbolic middle finger to local city planners.

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

A scattered trail of street art adds a pop of color to the city's stark structures.

This home on a quiet suburban street is completely covered with vibrant mosaics.