Legend has it that this bronze orb, which sat atop an ancient Egyptian obelisk, once held the ashes of Julius Caesar.

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

A massive marble foot is tucked away in a small alley near the Pantheon.

An ancient Roman temple first dedicated to an emperor's wife is now a church.

This statue is the only female representation of Rome's "talking statues."

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

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

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

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

A monumental fountain in Rome features a large statue of Moses that has been criticized for centuries.

Architectural monsters are devouring this palace's every door and window.

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

This monumental fountain has moved around the city multiple times.

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

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

A special area of the National Archaeological Museum of Naples is located inside a metro station.

A rococo room covered entirely in porcelain originally constructed for another royal residence.

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

These bronze horses on the gates of the Royal Palace of Naples were a gift from a Russian tsar.

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

A Greek tomb discovered under a palace in Naples displays ornate funeral decorations.

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

This whimsical fountain depicts a winged siren shooting water out of her nipples into the fires of Mount Vesuvius.

San Gennaro, the patron saint of Naples, greets pedestrians between these narrow city streets.