Vines grow up the metal bars in this public park created from an old machine factory.

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

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

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

Artists and musicians now rule over this former rail station.

This secret garden has bloomed into London's most unique hub of urban creativity.

A kaleidoscopic warehouse-maze of handmade neon signs.

A hands-off space for graffiti artists to hone and display their skills.

This 1920s Dutch barge is now a floating bookstore.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

A student driver's nightmare.

An art world insider finds himself battling for his artistic home.

A colorful piece of contemporary art cheerfully clashes with Lyon's historical architecture.

Lyon, France is home to two remarkably preserved Roman theaters, one dating back to 15 BCE.

The celebrated eyesore created by starry-eyed sweethearts.

This Parisian gem is one of the most incredible ethnographic museums in the world.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Abandoned railway line circling the city of Paris.

An eclectic sculpture park rises atop a giant pile of ashes in Sweden.

This secret facility trained seals for the Swedish navy during the Second World War.

This abandoned urban warfare facility is a dream come true for airsoft and paintball enthusiasts.

These miniature works of art are hiding in plain sight on buildings around the city.

A colossal strolling Pinocchio that was greeted with more outrage than whimsy.