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

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

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

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

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

This ancient Roman arch misled treasure hunters for centuries.

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

This ancient trail climbs the mountain where a Latin League cult worshipped Jupiter, its main deity.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

This large, circular tomb is the final resting place of the first emperor of Rome.

Ancient ruins hidden underneath a modern luxury hotel.

Gods clash with machines in a power plant regenerated as a museum.

A treasure trove of Renaissance-era funerary art in a Roman church built on top of Nero's grave.

A huge enchanting public park just outside the ancient walls of Rome.

Rome's ancient Etruscan rival, now a park full of ruins.

The studio built by fascists in the hopes of "reviving the film industry" with the occasional propaganda film opportunity thrown in.

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

This hill made entirely of ancient Roman jars was simply a garbage dump to the people of the time.

More sculpture than building, this architecturally significant temple was built on the spot of Saint Peter's crucifixion.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

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

A Nesting Doll of Churches.

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.