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

The Pope’s secret escape route.

An unremarkable wooden wheel built into the side of one of Rome's oldest hospitals was part of a policy to reduce infant exposure.

Architectural monsters are devouring this palace's every door and window.

Rome's first modern graffito is all that is left of a peaceful protest from the 1970s.

This small Roman arch was transformed into a dwelling by the founder of the Trinitarian Order.

This statue is the only female representation of Rome's "talking statues."

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

Also known as the Square Colosseum, this building is a prime example of fascist-era rationalist architecture.

This gallery commissioned by Cardinal Spada is known for its magnificent optical illusion.

Charles Dickens was not a fan of the ghastly wall dressings in this 6th century church.

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.

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

In Rome’s Jewish ghetto, a 200-year-old bakery still makes the neighborhood’s historic sweets.

This ancient market is often referred to as the oldest shopping mall in the world.

Believed to be the remains of the lost Temple of Minerva, this nymphaeum has been known by its misnomer to this day.

An alchemist's "magic door" stands in the middle of a Roman park.

Stone memorial that's said to predict the death of the pope and the site of the Cadaver Synod.

Ancient ruins hidden underneath a modern luxury hotel.

This hidden alley near the location of Rome's first theater was the site of a curious miracle.

An 18th century fountain and two columns are all that remains of Rome's forgotten river harbor.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

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