An Irish Memorial commemorating those who perished due to potato blight.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Utopia and nostalgia mingle at the site of Bronson Alcott's ill-fated agrarian commune.

Mass Grave of 48 colonists killed in a raid by Native Americans and the French in 1704.

The prototype for all Nazi concentration camps.

Horrifically creative torture devices and shame punishments line the walls of this chilling museum.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

One part local history, 99 parts gruesome haunted house.

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

These steps offer a breathtaking view of one of Europe's most besieged fortresses.

A book bound in the skin of an infamous criminal, along with countless other specimens.

There are plenty of wonderful panoramic vistas in Edinburgh, but not many are hidden smack in the middle of the Old Town.

This early version of the guillotine was used to execute the man responsible for its construction.

Tiny effigies of the victims of Edinburgh's famous Anatomy Murders.

The tomb of one of Scotland's bloody historic villains is a magnet for bumbling desecrators.

Protecting the dead from opportunistic body snatchers.

The most loyal of little dogs, or a Victorian era publicity stunt?

This small museum in a 17th-century building honors three iconic Scottish writers.