Diver Uncovers Massive Roman Coin Hoard Off Sardinia — Could a Lost Shipwreck Lie Nearby?

A recreational diver off the coast of Sardinia has uncovered an extraordinary scatter of ancient coins that may point to a long-lost maritime wreck. The discovery, made near the town of Arzachena, began when a glint in seagrass revealed a single coin — and then tens of thousands more.

Authorities from Italy’s culture ministry say the hoard consists of bronze and copper follis coins minted in Rome and dated to roughly 324–340 AD. Based on the weight and spread of the material on the seabed, experts estimate the total could be between 30,000 and 50,000 coins, making this one of the largest numismatic finds in recent decades.

At the time of the find, divers were trawling a sandy patch ringed by seagrass close to shore. The coins are reported to be in an "excellent and rare state of preservation," a detail that has intensified interest from archaeologists and conservators.

Researchers say the concentration of coins — together with rows of narrow-necked, two-handled amphorae recovered nearby — strengthens the hypothesis that the hoard may have come from a single maritime cargo, possibly a shipwreck that has not yet been identified. Local underwater conditions are favorable for preserving ancient wrecks, and teams are hopeful that further survey work will reveal structural remains.

"The treasure found in the waters of Arzachena represents one of the most important discoveries of numismatic finds in recent years," said Luigi La Rocca, Director General of Archaeology, Fine Arts and Landscape for the region, in a statement translated from the Italian culture ministry.

Recovery and protection efforts were launched immediately after the discovery. The response included the ministry’s undersea archaeology department, the art protection squad, firefighter divers and border police divers, who secured the site and began preliminary documentation. Authorities stress that conservation, cataloguing and careful archaeological survey will be necessary to preserve the material and properly interpret its context.

If a wreck is found, it could shed light on late Roman maritime trade and coin circulation during the transition from the Roman Empire to the Byzantine period. For now, researchers and the public alike can marvel at the scale of a find that offers a rare window into the ancient Mediterranean world.