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

Every day is like Christmas on this street where the traditional Neapolitan nativity scene comes to life.

The relics of dozens of martyrs are stored in a single chapel.

This 17th-century passageway is home to numerous bookshops, a witch legend, and the oldest pizzeria in the world.

A surreal botanical garden with an even more surreal tour guide.

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

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

The old church, buried by the 1784 Mount Vesuvius eruption, is a remarkably well-preserved place where people now pray for the souls of the dead.

The oldest volcanology research center in the world.

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Before it was buried by volcanic ash, this fast-food restaurant fed the hungry hordes of ancient Rome.

Buried next to Pompeii, this lesser-known Roman villa was the opulent vacation home of Emperor Nero's wife.

This tiny islet has somehow housed an ancient temple, two monasteries, a church, a fortress, and a restaurant.

For centuries, this large Roman villa remained hidden thanks to the eruption that buried nearby Pompeii and Herculaneum.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

A narrow opening between the mountains of the Amalfi Coast creates a scenic hidden beach.

A limestone grotto where daylight filters in from below and turns the water a beautiful turquoise. Also home to a small underwater nativity scene.

Amalfi's pre-industrial history is slowly being engulfed by the lush vegetation of the Ferriere Valley.

Beautiful views and Roman-style statues on the Italian coast.

This seaside Italian village doesn't just look Escher-esque, it actually inspired the mind-bending artist.

A beautifully well-preserved ancient Roman villa.

According to the legend, this structure was built in a single night with the help of the devil.

During World War II, the Shroud of Turin was secreted to this remote southern Italian complex.

Geometry and mystery come together in an epic show of octagonal masonry.