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

Legend says this mysterious stone head belongs to a woman who was petrified by an alchemist.

An incredible menagerie of more than 3 million taxidermied animals at the oldest science museum in Europe.

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

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

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

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

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

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

This Roman arch marks the location of an ancient gate at one of the Seven Hills of Rome.

These "anatomical machines" are only one of the many strange items in this Italian crypt.

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

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

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

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

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

Crushed coral and crystals give the sand its signature coloration.

This centuries-old Italian chapel hangs midway down a sheer cliffside.

The martyr's wax-enhanced skeletal remains lie preserved in a glass case in the Santa Maria della Vittoria in Rome.

A collection of objects supposedly singed by the hands of souls in purgatory.

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

Over 50 exquisite hand-painted Renaissance maps decorate a Medici storage room.

Drink wine handed out through a window as part of an age-old tradition.