Ancient ruins hidden underneath a modern luxury hotel.

A modern sliver of architecture in Roma.

The ruins of an abbey believed to have been founded by Charlemagne in the 9th century.

Its interior is adorned with some of the best examples of early Christian mosaics.

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

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

Known for centuries as the famous Roman emperor's burial place, this monument is actually something else.

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

This Italian stadium makes liberal use of fascist statuary to evoke classical sporting arenas.

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

Hidden within this iconic mountain are a set of World War II bunkers once used by German forces.

Rome is now home to a stunning food museum and library.

A monumental fountain in Rome features a large statue of Moses that has been criticized for centuries.

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

One of Rome's most picturesque and original bridges was also a popular choice for Grand Tour artists.

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

An abandoned 17th-century baroque hunting lodge with a wonderfully strange architectural plan.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

According to local folklore, this Roman sepulcher was once a throne for the Devil.

Italian horror legend Dario Argento’s own shop hides a sinister museum-dungeon in the basement.

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

The Italian revolutionary's legendary wife is portrayed on horseback waving a gun and holding her child in this memorial on the Janiculum.

An oasis of beauty, tranquility and botanical research in the middle of Rome.

A small cell adjacent to this church was once the bedroom for a renowned saint.