Venice's "Island of the Mad."

The doodles of a genius line the walls of a secret room under the Medici Chapel, where they were hidden for nearly 500 years.

According to the local folklore, the myriad colors of this lake are the result of a lovelorn wizard's blunder.

Thousands of well-dressed mummies below a monastery.

Stalactites and stalagmites in a beautifully lit cave.

Pompeii's less famous neighbor is still revealing her secrets.

Renaissance villa and gardens complete with a tormented colossus.

The middle finger of modernity.

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

A 16th-century horror show built in a lovely Italian garden.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

Rome's first modern graffito is all that is left of a peaceful protest from the 1970s.

Plaques on its facade commemorate the Tiber's most destructive deluges.

A statue representing a lost Roman profession that was vandalized for centuries.

Inside this McDonald's you can dine on your Big Mac and fries next to a 2,500-year-old Roman wall.

This hidden alley near the location of Rome's first theater was the site of a curious miracle.

Its interior is adorned with some of the best examples of early Christian mosaics.

A wunderkammer of curious objects and intriguing art nestled within a hub of ancient Roman sites.

Remnants of a 4th-century church with vivid medieval frescoes and ancient sarcophagi hide beneath this old basilica.

This park on the outskirts of Rome boasts two ancient Roman aqueducts and a medieval tower.

The ruins of an abbey believed to have been founded by Charlemagne in the 9th century.

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

Roman-era ships unearthed...

St. Francesca Romana, patron saint of drivers, resides in the church she founded.