The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

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

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

The "Greatest Sewer" of ancient Rome is one of the oldest sewer systems in the world, and is still in use.

The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

This is the oldest Roman-made bridge in the city still existing in its original state.

In the early Roman Empire, people deemed traitors and criminals were tossed to their deaths from this rock.

The remains of this 2nd-century Roman temple are incorporated into a modern building.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

This hydrochronometer was invented by a Dominican monk and is a prime feature in this garden.

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

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

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

The spot where the fascist dictator made some of his most famous speeches including declaring war on Britain and France.

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

An 18th-century post box used to alert the church of sick and ailing foreign pilgrims.

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