Rescue excavation of a 1,600-year-old Roman merchantman
After winter storms scoured away sand from around the ancient harbor of Caesarea Maritima, Israel, local scuba divers came across the remnants of an ancient Roman merchant ship scattered across an area that was 40 by 60 meters. It was a discovery heralded around the world as the largest shipwreck found in Israel in more than thirty years, but that was only as the rescue excavation began. It soon became clear that the site was one of the largest and most important late Roman wrecks ever discovered.
During the brief time the shipwreck was exposed, from May 2016—June 2017, a mapping and surface recovery operation was led by Jacob Sharvit, Head of the Marine Archaeology Unit of the Israel Antiquities Authority (IAA), with Dr. Bridget Buxton of the University of Rhode Island. Oceangate Foundation was among the key supporters who made this expedition possible, and facilitated the testing of new prototype 3D site mapping robots and technologies from the Universities of Girona and Zagreb. These new technologies produced data and images for a 3DVR experience of the shipwreck site.
Caesarea’s early fourth century AD shipwreck reveals the world of Rome’s first Christian emperor, Constantine the Great, and his arch-rival Licinius— both of whom are featured on many precious coins from the site. After only a few weeks of investigation, it had already yielded the largest shipwreck assemblage discovered in Israel in more than a generation, including over 30 kg of coins, many luxury goods of Italian and Egyptian manufacture, bilge parts, sheathing, anchors, a unique lead brazier, a large steelyard, a bronze cupid, fishing equipment, ornate bronze lamps and figurines, glass cullet (the largest provenanced collection of late Roman glass in the world), marble architecture— possibly associated with a shipboard shrine of Isis, Italian decorated lead mirror frames, copper nails and tools, and five fragmentary life-size bronze statues. Almost 2000 kg of raw material was recovered, including 500 kg of iron, 800 kg of bronze statue parts, 150 kg of glass, and other artefacts that suggest the ship began her journey in Ostia, Italy, and came to Caesarea via Egypt. Treasures from the wreck have already toured museums around the world, and are displayed now in Caesarea’s new archaeological museum.
Rescue excavations occur when archaeological sites face imminent destruction—in this case, due to the sudden exposure of a long-buried shipwreck through natural processes. During this thankfully brief period of exposure, the project’s prototype site-mapping robots were able to create fast, accurate photomosaics and 3D models of the site to assist the archaeologists doing the recovery operation.
It is only a matter of time before storms and erosion expose this site again, potentially causing catastrophic damage to delicate organic materials and other treasures. A planned systematic excavation of the site over several years could save the rest of Caesarea’s unique fourth century AD wreck for posterity, as well as providing further field-testing opportunities for new robotic archaeological tools.
The IAA maritime unit monitors areas that were at-risk sites after storms, and attempts to respond quickly to remove artefacts in rescue excavation scenarios. The full excavation of such a large and significant site would be an expensive multi-year undertaking by many partners, so in situ preservation (leaving a shipwreck untouched) is the best option as long as the site remains naturally buried.