Two protected wreck-sites off Chesil Beach in Dorset are enabling local divers to work as marine archaeologists.
The Nautical Archaeology Society (NAS) and Maritime Archaeology Trust (MAT) are hoping to find out more about the mysterious sites through a week of fieldwork, after which they will leave the amateur team they have trained to continue the investigation.
The Chesil Cannon sites lie 300m apart at depths of around 12m.
Site 1 is thought to date from the late-17th/early-18th century and includes the remains of eight cannon, iron shot and timbers.
Site 2, which might be 17th century, has seven cannon but few other artefacts visible. The two sites could be parts of the same wreck, but 10 years of diving on them has so far failed to establish their identity.
During the summer, local dive-club members and individual divers attended free training in underwater surveying techniques, recording of cannon and photogrammetry to prepare them for their archaeological task.
As a qualified local team they can carry on investigating and protecting the wrecks, which can be dived only under an Historic England licence.