BALIKESİR A 1,500-year-old trade shipwreck has been discovered off the coast of Ayvalık in Türkiye's Balıkesir province as part of the "Turkish Shipwreck Inventory Project: Blue Heritage." Using domestically designed and produced robotic underwater vehicles, researchers identified the wreck 2.5 miles off the coast. Dating to the late fifth century, the wreck contains approximately 10,000 ceramic plates and is described as the largest "plate shipwreck" found in the Aegean and Mediterranean seas.