Cog once again in the spotlight
22 October 2020 11:10
Photo: Johan Rönnby.
25 years ago, a well-preserved medieval cog was discovered on a golf course on the island of Gotland. The so-called Kronoholm cog has been recently reexamined. Archaeologists have discovered that it has been attacked, and that the cog may now be threatened. New samples have been taken to find out whether it is a Gotland cog.
When a water pond was about to be built on Kronholmen’s golf course outside Västergarn 25 years ago, a well-preserved cog was found that made headlines. At the time, young archaeologists dug out a trench and took C14 samples of the wood. The cog turned out to be from the early 13th century.
Now the same archaeologists are back on the scene. Charlotte Björdal, professor in conservation at the University of Gothenburg, and Johan Rönnby, professor in maritime archaeology at Södertörn University are surveying the condition of the cog together with other archaeologists.
“The cog isn’t doing so well. A lot has happened in 25 years, and wood samples that were deposited back then have been attacked,” Johan Rönnby says.
He says that it is gratifying that everyone, not least the owners of the golf course, are in favour of the survey.
“I hope we get the chance to excavate this medieval cog in the future,” he says enthusiastically.
Cogs are not a common find. This one, which is built using both oak and pine, is very rare. German cogs were built entirely of oak.
“So, it could therefore be a Gotland cog,” Rönnby says.
New wood samples have been taken to study the tree rings, which can provide answers about where the wood grew and what year the trees were felled. Some bone residue and something that is probably burnt lime have also been found.