An ancient Viking runestone hidden in plain view in Stockholm's old town.

Now a hotel, this former bank was the site of a robbery that spawned a psychological phenomenon.

This Stockholm light tower can be controlled by anyone with a smartphone.

A hidden bathhouse in one of Stockholm's oldest and busiest neighborhoods is open to anyone who can find it.

A tombstone on the grounds of the royal castle marks the burial site of a Swedish king's beloved dog.

A simple stone remembers one of the most menacing horses in the Swedish military.

Early habitat dioramas and home of the elusive gaff, the skvader.

This legendary dessert was served to Nobel laureates for decades.

A Stockholm metro station is home to an escalator that is not only the longest in Sweden, but among the longest in the world.

A 130-year-old urinal is the oldest of Stockholm and perhaps all of Sweden.

This now abandoned restaurant provides some of the most amazing views of Lisboa.

An early Portuguese serial killer's head is alarmingly well preserved in a jar at the University of Lisbon.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

A preserved oak tree about 3,500 years old found in Riga, Latvia.

A century-old tradition has culminated in a small but singular collection of feline effigies.

The giant birds honor two native North American species.

This informal museum is a magical trove of anonymous art collected from car boots and flea markets.

A traditional American farmhouse plopped in the middle of a Piccadilly courtyard.

Since 1874, this macabre collection has developed into a museum devoted to Scotland Yard's mementos of dastardly deeds.

"Purveyors of traditional sweets and vintage treats."

A faded reminder of what was once a common sight in London during the Blitz.

Its collection includes a broad array of social, geographic, graphic design, and political history.

This toxic spoil heap found a second life as a ski slope, popular film location, and wildlife haven.

The next-door homes of two very different musicians, George Frideric Handel and Jimi Hendrix.