The experimental test tracks of a retro-futuristic monorail still stand in the French countryside.

Abandoned Nazi train station turned underground astroparticle laboratory.

An underground city of ancient quarry tunnels hid thousands of Allied soldiers in WWI.

This disused boat elevator was saved from the scrap heap so that visitors could tour its rusting skeleton.

An undulating wicker beast looms peacefully atop a sand dune in Belgium.

These crumbling Nazi artillery bunkers are now fair game for massive graffiti projects.

A Cold War command center is hidden under an idyllic countryside.

This Belgian theme park began as a refuge for bored church children and was closed down when a boy lost an arm.

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

Massive puppet-automaton machines created by French artist collective Machines de l’Ile.

An aluminum skeleton brings Chinese mythology to the French shore.

A mosaic-tiled house built by graveyard sweeper Raymond Isidore.

A beautiful and classically designed villa, with an hourly infestation of monsters.

The Sun King's military models, saved from the Louvre.