The dance of this huge clock is a magnificent and eerie commentary on good and evil in the history of humankind.

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

Protecting the dead from opportunistic body snatchers.

Many of Edinburgh's more unsavory characters spent their final days behind this door while awaiting their executions.

The location of a citizen uprising that led to a gruesome act of mob justice.

Possibly the world's smallest museum is home to one exhibit that sheds light on the capital city's dark criminal history.

This cannonball embedded in the side of an Edinburgh house once served a surprisingly pedestrian purpose.

The final resting place of soldiers' loyal canine companions.

A six-ton wedding present for the King of the Scots.

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

Saint Joseph was said to heal the deaf and blind, but it was a much smaller miracle that got him canonized.

On the wall of this medieval walkway, a symbol of the Spanish Inquisition.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Possibly the oldest church in Barcelona, this basilica has its pagan and Christian mythologies all mixed up.

This fountain was designed to honor the man who helped bring water to Barcelona.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

The curios of pharmacist and collector Henry Wellcome.

The ceiling of this shopping arcade is adorned with six trompe-l’œil artworks, including a grim funeral scene.

A gigantic mechanical bull rages over unsuspecting passengers at Birmingham’s central station.

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

A free public golf course hides in plain sight in the heart of Scotland’s capital.

A rare remnant of an exposition that took place nearby at the end of the 19th-century.

This historic pub has maintained much of its 1906 decor, including a small sequestered room for women, where orders were slipped through a tiny window.

A building-sized painting of the renowned 19th-century American abolitionist.