Abandoned railway line circling the city of Paris.

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

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

This path is named for a mythical half-boar, half-deer creature that once roamed the Green Mountains.

This natural "sea of stones" was once used by the Romans as a quarry.

The stunningly blue waters of these beautiful caves also have a violent past.

This small sculpture honors a shuttered bookshop that was the site of a fiery act of protest.

This former brickworks pit is full of legends about its murky depths.

This woodland area is a lasting tribute to the Queen Mother.

This outdoor observatory offers stellar views and a scale model of our solar system.

This interactive sculpture allows visitors to leave a message in case a friend passes by.

An abandoned village where the ruined foundations cling to a cliff.

This massive, beautifully-lit underground quarry leaves visitors in awe.

A beautiful, historic location open to the public.

These precariously placed ruins harken back to a 13th-century castle.

This once-popular otherworldly landscape was formed by one of the largest volcanic eruptions in history.

Visitors to this shop will find fossils, minerals, meteorites, skeletons, oddities, and much more.

Abandoned businesses, homes, and rusted cars are all that remains of this stopover town.

This former train tunnel is filled with lines from a poem crafted by Robert Louis Stevenson.

An eerie reminder to the horrors of World War II.

This advertisement for talcum powder was painted on the rock face and has since defied removal.

A rare survivor from the age of plagues.

This peaceful oasis appears dreamy, but it's also the site of a nightmarish legend.

A collection of trees from various corners of the world call Stockholm University home.