A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

The hidden lair of an alchemist rediscovered in a 2002 flood.

An abandoned underground bathroom is now a space for public art.

Hamburg's first legal sex work is relegated to a gated street that still does not allow pedestrian women.

Finland's oldest astronomical observatory once played a crucial role in seafaring and timekeeping.

Where once there was a train station bathroom, there is now this German burger joint.

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

A magnificent tomb that was the final resting place of the Dukes of Hamilton.

A watering hole from the late 1800s in the heart of the Campsie Fells.

A beautiful Greco-Roman structure houses a well once believed to have healing powers.

A recreation of pop art pioneer Eduardo Luigi Paolozzi's London studio.

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

Scotland still bears an enormous scar of its Roman past.

Andrew Carnegie funded the building of almost 3,000 libraries across the world, this was the first.

Legend says this rock was once a chopping block for public executions.

It's said this was once the home of King James V's pet lion.

This pyramid is dedicated to all those who suffered martyrdom for civil and religious liberty in Scotland.

The main residence of the Erskine family and the hereditary keeper of the nearby royal Stirling Castle.

Tucked away in this local museum is a piece of sporting equipment that dates to the 16th-century.

Hidden in this modern shopping center is a relic of 16th-century capital punishment.

An Italian restaurant became a rock-and-roll hangout and the lair of the "Hollywood vampires."

This abandoned hospital village was once viewed as an innovative way to deal with mental illness.

A giant pineapple, a symbol of hospitality, and an amazing vacation rental option.