A Nesting Doll of Churches.

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

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

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

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

A fairy tale castle in modern Rome.

Jesus' footprints and the first catacombs in the world.

2300-year-old Roman road connecting the empire.

The underground sanctuary of a mysterious ancient cult.

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

An alchemist's "magic door" stands in the middle of a Roman park.

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

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

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

Architectureal fantasy quarter of Rome.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

The final resting place for the remains of 143 Habsburg royalty.

This odd Chilean waterfall-cano hotel must be entered via a rope bridge.

Ancient, mysterious stone altars are hidden among wild woods in central Italy.

What appears to be an ancient Roman temple is actually a Catholic church.

This region of the Perugia municipality has an unforgettable name.

The eerie ruins of this feudal fortress witnessed the execution of 60 conspirators in 1387.