About 2,000 years ago, during the Roman empire, Pozzuoli was a bustling, commercial city equipped with a port that facilitated international trade. The city ultimately declined with the fall of the Roman empire at the end of the fifth century, according to Britannica. Since then, parts of the once-thriving cosmopolitan center have been overtaken by the Gulf of Naples, leaving ruins of the people who once lived in the city submerged in the water.

Since the 1800s, the port’s seabed has been a rich site for unearthing Roman ruins and artifacts, including slabs with inscribed dedications to deities, according to a news release from Italy’s Ministry of Culture. The latest discovery in the city includes a temple and two marble altars that once belonged to the Nabataean people, the ministry said. Experts dated the altars to the first half of the first century.