Rione Terra is Pozzuoli's oldest quarter and its ancient acropolis. The original 2nd-century-BC temple to Jupiter, Juno and Minerva was replaced by a temple to Augustus in the 1st century. The latter's marble columns now form part of the 17th-century Duomo, home to 13 paintings by 17th-century greats including Artemisia Gentileschi, Giovanni Lanfranco and Jusepe De Ribera. Below the current cluster of buildings is a trove of an ancient ruins.
Dating back to when Pozzuoli was the ancient port of Puteoli, the ruins include the decumanus maximus (main street), flanked by ancient taverns, millers' shops (complete with intact grindstones) and graffiti written by the poet Catallus in a slaves' cell. Archaeologists made the startling find after volcanic activity in the 1970s forced a mass evacuation of the quarter.