An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

A magnificent waterfall is also home to the remains of a Roman hydraulic engineering system.

This ancient Roman prison is decorated with an upside-down cross not as blasphemy but as saintly tribute.

A fairytale island floats in the middle of Italy's little-known Lake Orta.

Hanging within this medieval church are the bones of a beast allegedly slain by a fourth-century saint.

Medieval town turned hippie commune, once home to the secret foreskin of Jesus Christ.

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

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

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

This Tuscan lake hides a 13th century town that is still visible when the water recedes.

The graveyard is filled with beautiful funerary art and boasts breathtaking views of Florence.

The Sighignola summit on the Swiss border offers views so breathtaking it's been named one of the most beautiful places in Italy.

Brass cobblestones mark the places where individual Holocaust victims were taken from their homes.

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

A sinister pyramid in the Frari contains the heart of the famous neoclassical sculptor.

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

The plague quarantine island home to the alleged "Vampire of Venice."

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

This private skyway is filled with art and was expanded explicitly so that Hitler could appreciate a river.

Filled with goldfish swimming in a shallow pool of sea water, this ancient crypt is more wishing well than burial site.

One of seven Jewish catacombs in Rome and one of only two open to the public.

This magical-looking island is notorious for the misfortunes suffered by its owners.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

This sword isn't waiting for a king to pull it out. It was placed there by a saint.