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

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

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

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

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

The walls and streets of the ancient city are peppered with penises.

Erotic art covers the walls of the largest ancient pleasure palace.

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

Medieval torture techniques with a modern conscience.

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

Ancient snack bar of the Roman Empire re-opened.

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

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

Jesus' footprints and the first catacombs in the world.

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

As can be expected from a centuries-old church built in a canal city, the undercroft of this house of worship is beautifully flooded.

2300-year-old Roman road connecting the empire.

The underground sanctuary of a mysterious ancient cult.

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

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

Named in tribute to Canadian singer and songwriter Neil Young.

Beautiful scenery, history, science, and physics come together in this remnant of shipping lore.

This 1836 church, constructed by formerly enslaved people, honors a leader in Afrocentric music.