Cog on signet from the medieval Stralsund in northern Germany, from the year 1329.
During the autumn, the University of Gothenburg conducted maritime archaeological surveys along the coast of Bohuslän to find out more about known wrecks. At Dyngö outside Fjällbacka, they enlisted the help of drones and discovered a dark structure in a natural harbour near land. While diving at the scene, they found a previously unknown wreck that turned out to be a cog ship. The wreck is 10 metres long and 5 metres wide.
“The ship’s side is sealed with moss, which is typical of cogs, and it was once likely 20 metres long,” says Staffan von Arbin, the maritime archaeologist who led the excavations.
Wood samples were taken and sent to a dendrochronology laboratory in Denmark. The results came in, and they were nothing short of astonishing. The wood in the cog is made of oak and was carved in northwestern Germany between 1233 and 1240.
“The cog may have been built in the region around Bremen, and belonged to the growing German Hanseatic League. It is one of the oldest cogs ever found in Europe,” von Arbin says with much enthusiasm.
The German Hanseatic League traded along the Norwegian coast and throughout the Baltic Sea during the Middle Ages. Bohuslän, which was then part of Norway, was an important thoroughfare for international shipping during this period.
A ceramic shard in younger grey ware was the only object found during the limited investigation. It confirms that this is an early medieval find. A possible future excavation might be able to uncover more traces of the ship’s cargo.
“Inside, the ship is filled with charcoal. This is an indication of a powerful fire which caused the ship to sink to the bottom, where it has now remained for nearly 800 years,” von Arbin concludes.
Staffan von Arbin is writing a thesis on medieval shipping in Bohuslän, which in the Middle Ages belonged to Norway. Thanks to the finds discovered this autumn, he can now tell us about wrecks and ships from the year 1230 to the early 1500s found in the area from Gothenburg to the Norwegian border.
