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

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

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.

The Neapolitan Cult of the Dead still cares for the skulls at this mini-Fontanelle.

An unusual "skull with ears" sits in the crypt of this small church tucked away at the end of a narrow alley.

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

Perhaps the most spectacular grotto along the Algarve coastline.

The Italian revolutionary's legendary wife is portrayed on horseback waving a gun and holding her child in this memorial on the Janiculum.

A burial vault located under Tiber Island in the middle of the Italian capital.

A forgotten "city of water" underneath the famous Trevi district.

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

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

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

The final resting place of the poets Shelley and Keats.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

Architectureal fantasy quarter of Rome.

The yawning maw of this pagan visage is said to bite off the hands of liars.

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

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

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

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

The remains of the left arm of the levitating philosopher-saint are kept in a 13th-century Neapolitan basilica.

The largest and most famous wax anatomical collection anywhere in the world.