A strange rock with a sinister reputation lurks within the crimson waters of this Scottish glen.

A 150-year-old steam locomotive crosses the southern half of the island daily.

The enormous earthwork sculpture honors the ponies that lived and worked in the old colliery.

The largest cave chamber in Britain—big enough to fit a whole cathedral inside.

This centuries-old Italian chapel hangs midway down a sheer cliffside.

Inside a former cabaret, seven floors of erotic art.

This off-limits room in the National Library of France is home to a system of pneumatic tubes, once used to bring books to readers.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

Abandoned railway line circling the city of Paris.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.

Ancient ruins hidden underneath a modern luxury hotel.

Hans Christian Andersen for the postmodern world.

Museum dedicated to the terror regimes of Hungary.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

A stairway to heaven, or to nowhere at all.

Single runway interrupted by a busy road that cuts across its middle.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

An interactive exhibition space dedicated to the kinetic sculptures of Swiss artist Jean Tinguely.

This species of wild goat stars in witchy legends and frolics among the park's eerie rock formations.

Hidden well off the beaten path in Catalonia is this crumbling medieval castle that is slowly being covered in graffiti.

This abandoned mansion has a window for every day of the year, and is a temple for ghost hunters.

The four-story mural is the centerpiece of a lavish hotel's lush atrium.

A small town celebrates its cash crop with a giant highway sculpture.

This art installation at an abandoned lipstick factory has distinct anti-capitalist vibes.