This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

Head underground and take a tour of the city's working sewer system, and see the underground river Senne, which defined Brussels for centuries before being covered in the 19th century.

The marble facade hides a little-known medical museum with early surgical instruments and rare copies of canonical texts.

A new sculpture calls attention to climate change in the centuries-old city it threatens.

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

One of the oldest medical collections in Europe focusing on rare surgical instruments.

Outdoor art exhibition made of classic Tetris pieces.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

The curios of pharmacist and collector Henry Wellcome.

A measuring mishap led to these artificial stone ladies losing their stomachs.

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

This small museum tucked within a subway station holds pieces from Madrid's past.

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

A tiny, heartwarming piece of art hiding in plain sight.

A giant wooden soda bottle pays homage to a distinctly British drink on the very spot where it was invented.

This tiny watering hole claims to have the smallest bar counter in Europe.

Have a seat with the father of modern computing at this Manchester monument.

This dreamy street will transport you to wintertime in Victorian England.

This Manchester laundromat is hiding something.

These lovely Turkish-styled baths were brought back to life after winning a reality show competition.

Dating back almost 400 years, the oldest public collection library in the United Kingdom was once the study hall of Karl Marx.

Tucked in the back of a flower shop, its collection details the fascinating history of the Netherlands's iconic symbol.

This pirate-broadcasting-tower-turned-restaurant played a rebellious role in the history of Dutch television.

This subterranean studio is filled with fascinating kinetic art.