A shipwreck discovered off the coast of Copenhagen has been identified as a cog, a medieval cargo ship, of massive dimensions. Approximately 90 feet long, 30 feet wide and 20 feet high when intact, the ship had an estimated cargo capacity of 300 tons. It was built around 1410, and is the largest cog ever found.Cogs were designed to be highly navigable, even when fully loaded with bulky cargo. They were strong enough to make it through the treacherous waters of the Baltic even with a small crew. They were the draft horses of maritime trade in medieval northern Europe.The wreck was discovered by divers surveying the seabed in the Svaelget, the strait between Denmark and Sweden. It is the second ship found in the area, earning it the moniker Svlget 2. It is an exceptional state of preservation, protected by a layer of sand covering the starboard side.Dendrochronological analysis shows that Svlget 2 was built around 1410 using timber from two regions: Pomerania, which is modern-day Poland, and the Netherlands. By comparing tree-ring patterns with reference data, researchers were able to date the wood and determine its origin. The planks were made of Pomeranian oak, while the frames the ships ribs came from the Netherlands. This construction pattern suggests that the heavy planking timber was imported, while the frames were cut locally at the building site, reflecting a practical approach and a complex trade network where large quantities of timber moved across Northern Europe.It tells us that timber exports went from Pomerania to the Netherlands, and that the ship was built in the Netherlands where the expertise to construct these very large cogs was found, says maritime archaeologist Otto Uldum.A number of first-time archaeological discoveries have been made in the exploration of the Svlget 2 wreck. One exceptional find is the remains of the castle on the stern of the ship. Castles were covered platforms built on the bow and stern of medieval cogs. The crew could shelter there during bad weather, granting them a measure of protection that open Viking Age ships could not provide. Previously they were only known from contemporary illustrations. This is the first archaeological evidence of a cog castle ever found.Another stand-out find was the ships brick galley, where the crew cooked over an open fire, the earliest example found in Danish waters.Around 200 bricks and 15 tiles formed the galley, and in the same area archaeologists found bronze cooking pots, ceramic bowls and remains of fish and meat.We have never before seen a brick galley in a medieval ship find from Danish waters. It speaks of remarkable comfort and organisation on board. Now sailors could have hot meals similar to those on land, instead of the dried and cold food that previously dominated life at sea, says Otto Uldum.In the galley area, archaeologists also uncovered parts of the crews tableware and the pots used for cooking, as well as remains of provisions such as fish and meat and hundreds of finely cut sticks that may have been used for stockfish.Alongside the galley equipment, archaeologists also found artifacts from the crews daily life, including a painted wood plate that is the only one of its kind from the era found in Denmark, shoes, combs and rosary beads. They did not find any remains of cargo, probably because the hold was not covered so its contents floated away when the ship sank.