Researchers Find Medieval Shipwreck in Norway's Largest Lake

In a survey of the deep waters of Mjøsa, Norway's largest lake, researchers working for the Norwegian Defence Research Establishment have discovered a historic shipwreck dating back to as long ago as the 14th century. 

A team hired by the agency has been mapping part of the 140-square-mile lake in high resolution using an off-the-shelf HUGIN autonomous vehicle (AUV). The mission objective is not to find shipwrecks, but to locate unexploded ordnance. Quantities of munitions were dumped in the lake over the years, and some could contain potential contaminants. The lake is an important source of drinking water for the population north of Oslo. 

But the same sonar technology used for searching the bottom for UXO is also quite good at finding marine wrecks, and researchers expected from the outset that they would encounter something interesting.

“We believed that the chance of finding a shipwreck was quite high, and sure enough, a ship turned up,” marine archaeologist Øyvind Ødegård of NTNU told Science Norway. 

The wreck is about 30 feet long, and it has characteristics that mark it as a medieval-era vessel, according to Ødegård - notably a stern-mounted steering oar.

Ødegård's survey continues, and NTNU plans to keep searching the lake in the coming years. There is every reason to suspect that more shipwrecks will be found, since the lake was used for commerce (and even inland naval battles) in the Middle Ages and earlier. The lake's cold, fresh water is an excellent preservative for wood, though iron fasteners will rust away.