The burial place of an obscure North African saint was turned into a macabre body preservation factory for the 17th-century Neapolitan elite.

Dug as a secret royal escape route, the tunnel became a wartime bomb shelter and dumping ground for vintage cars.

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

Skulls from the plague of 1656 and World War II bombings are united by a cult dedicated to caring for the ancient dead.

A labyrinth of ancient tunnels hidden below the city holds the ruins of 2,500 years of history.

An enigmatic modern marker left next to a historic Roman site.

This hermitage celebrates the legend of Emperor Constantine's healing from leprosy.

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

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

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

A rather vulgar example of the transition from Latin to the Italian vernacular.

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

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

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

Ancient ruins hidden underneath a modern luxury hotel.

One of the most important yet well-hidden museums dedicated to the history of medicine.

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

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

An abandoned Roman salami factory has found new life as an art space home to 200 squatters.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

This hidden Art Nouveau courtyard is an opulent feast for the eyes.

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

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

A Nesting Doll of Churches.