This hydraulic power system in London was, at one time, seen as a rival to electricity and the last of its kind to shut down.

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

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

London's only public statue of the much-married monarch adorns the gate to St Bartholomew’s Hospital.

A portly statue of a golden boy commemorates an unusual cause of the Great Fire of London: the sin of gluttony.

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

Taxidermied animals galore, by appointment only.

An eccentric 18th century naval officer built a ship's quarterdeck on his roof, the inspiration for Mary Poppins's "Admiral Boom."

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

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

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

A plaque hangs near the execution place of the Scottish Independence leader famously depicted in "Braveheart."

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

A glorious pub known for a spiteful printing feud and its famous typeface lost—then found—at the bottom of the Thames.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

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

A historic arboretum and non-conformist, non-denominational park cemetery.

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

Following the trail of an old metro line, this scenic path is haunted by a creepy spriggan statue.

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

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

Ring the bell to enter a bar that looks equal parts museum and old curiosity shop.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

This sweet-toothed bear searching for snacks has been a symbol of Madrid for decades.