a base with a dedication to emperor hadrian loses all shape at the top, like a half—melted candle.f zeus on his throne, dating to the first century bc, is covered with what looks like white scrawlings, the remnants of marine and crustaceans. but these organisms were not his only challenge. the zeus was likely stolen from the sea by looters. he wound up in the collection of the] paul getty museum in los angeles, acquired by a curator later indicted for conspiracy to traffic in illegal antiquities. he was returned to the campi flegrei museum in 2018. the other sculptures in the museum are now safe from marine organisms. but the artefacts that remain below the sea, including the precious floors that make up the largest collection of underwater roman mosaics in the world, remain at risk. finally it was time for me to go down and see it for myself. i was invited to join the team testing new technologies to help better monitor the erosion, but also to help the public engage with the site in new ways. chiara petrioli is professor of computer science at the university of rome. and the inte