An Italian ghost town that fought obscurity, until a mysterious illness brought it to its knees.

A huge enchanting public park just outside the ancient walls of Rome.

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

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

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

Jesus' footprints and the first catacombs in the world.

This beautiful park on the outskirts of Rome protects the ruins of two colossal ancient aqueducts.

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

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

The final resting place of the poets Shelley and Keats.

2300-year-old Roman road connecting the empire.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

The underground sanctuary of a mysterious ancient cult.

This gallery commissioned by Cardinal Spada is known for its magnificent optical illusion.

This hydrochronometer was invented by a Dominican monk and is a prime feature in this garden.

Hidden within this iconic mountain are a set of World War II bunkers once used by German forces.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

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

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

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

Derelict airplane bodies serve as both home and income for three Thai families.

The echoes of a railroad town that solemnly mark the end of the line.

The rocks in this arid basin leave trails of movement behind them.