Italian archaeologists have documented a submerged Roman bathhouse near Naples that they say may be the bathing complex of Marcus Tullius Cicero’s villa, the Campi Flegrei Archaeological Park announced Aug. 6.
The thermal complex lies roughly 10 feet underwater in the waters of Portus Julius, a harbor that became the first permanent Roman naval base. The site was first identified in 2023 and has been more fully recorded during recent diving surveys, park officials said. Current research, based on archaeological evidence and ancient sources, suggests the baths may be associated with Cicero, the Roman statesman and orator who lived from 106 B.C. to 43 B.C.
Park archaeologists described architectural and engineering features that date the complex to before the conversion of the area into a naval base in 37 B.C. The bathhouse preserves parts of a suspensurae system — a raised network of supports that allowed hot air to circulate beneath mosaic floors — and tubular structures running along walls that would have carried heated air. Those elements together produced a heated room comparable to a laconicum, an ancient Roman dry sauna, the archaeologists said.
Divers also recovered ceramic fragments that the park called "of particular importance," which may help researchers establish construction techniques and the circumstances of the site's destruction and submergence. Work will continue through the autumn, with teams focusing on restoration of a mosaic floor partly encrusted with mortar and on the conservation of small but significant traces of wall painting, the announcement said.
Portus Julius sits in the Phlegraean Fields, a volcanic region west of Naples that has a long history of coastal change. The harbor was created in the late first century B.C. as part of a naval development under the Roman Republic; earlier shoreline configurations and volcanic activity have left archaeological remains both on land and submerged. The discovery provides an uncommon opportunity to study a Roman heating system and mosaic work in situ, officials said.
Roman bathhouses served as social, hygienic and cultural centers across the empire, and archaeologists continue to find well-preserved examples in different parts of the Mediterranean. Recent regional discoveries cited by the park include a bath complex in Turkey that preserved original engineering details and a bathhouse re-used as a baptistery along Rome’s Appian Way.
The Campi Flegrei Archaeological Park emphasized caution in attributing ownership. "Current research suggests that we may be looking at the baths of Cicero's villa, known from historical sources," the park wrote in a translated social media post, but added that further study is required to confirm the identification. Archaeologists plan additional underwater surveys, material analyses and conservation work before drawing definitive conclusions.
The documentation of the bathhouse adds to ongoing efforts to map and protect submerged cultural heritage in the Bay of Naples. Park officials said the project will combine archaeological recording with conservation measures aimed at stabilizing mosaics and painted surfaces so that they can be studied and, where possible, made accessible to researchers and the public.
Further findings and formal analysis are expected as excavations and restorations proceed through the coming months. The park has posted photographs and preliminary reports online and plans to publish detailed results after laboratory study of recovered materials and completion of conservation work.