A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

A massive marble foot is tucked away in a small alley near the Pantheon.

Plaques on its facade commemorate the Tiber's most destructive deluges.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

Historic fortifications form the boundary of Vatican City, but it’s not entirely surrounded by walls.

These spartan apartments are provided to clergymen visiting Vatican City.

Breathtaking and huge 430 year old maps of Italy.

This small, ancient Roman temple was once a church dedicated to the patron saint of penitents.

This curious, round temple is the oldest still-standing marble building in Rome.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

The best preserved Paleochristian basilica in Rome hides a number of oddities and secrets.

The spot where Oxford garnered its name was also home to a medieval philosopher and includes a house covered in statues.

The shop where the girl who inspired the beloved character once bought sweets is now a book-themed commercial curiosity.

Hidden in plain sight, this creepy sculpture watches from above.

This small sculpture honors a shuttered bookshop that was the site of a fiery act of protest.

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

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

The final resting place of soldiers' loyal canine companions.

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

The 20th-century chapel’s intricate woodwork includes amazing details, most notably angels playing bagpipes.

Touching this 18th-century Scottish philosopher’s toe allegedly conjures good fortune.

A series of three shiny letters mark the boundary of an old refuge for those being pursued by debt collectors.

Anonymously sculpted and donated, these sculptures made from poetry books and pages are sprinkled around the city.