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Resting at the bottom of Mjøsa, Norway’s largest lake, a shipwreck from hundreds of years ago lies in near mint condition, frozen in time.
The vessel, with its unique stern posts and overlapping planks, reveals a moment in the lake’s maritime history and is estimated to date from between the 1300s and 1800s.
Investigators discovered the wreckage. during the execution of the Mission Mjøsa project, which aims to map the 140-square-mile (363-square-kilometre) lakebed using high-resolution sonar technology.
the Norwegian Defense Research Establishment he led the mission two years after conducting several inspections of remotely operated vehicles, or ROVs, in areas of the lake where large amounts of munitions had been dumped. The lake is a source of drinking water for about 100,000 people in Norway, according to the Norwegian University of Science and Technology, so the ammunition posed health risks. The wreck was seen during the inspection of the lake.
“My expectation was that shipwrecks could also be discovered while mapping the dumped munitions; that turned out to be the case,” said Øyvind Ødegård, senior researcher in marine archeology at the Norwegian University of Science and Technology and principal investigator for the mission. . . “It was purely that the statistical chance of finding wrecks that were well preserved was considered quite high.”
The newly discovered wreck lies at a depth of approximately 1,350 feet (411 meters) and was captured on sonar imaging, a system that uses sound pulses to detect and measure the area below the water’s surface. The images revealed that the ship was 33 feet (10 meters) long.
The freshwater environment and lack of wave activity at that depth had kept the boat in pristine condition, except for a few corroded iron nails at each end of the boat. For Ødegård, the weathering of the metal is a clear indication that the wreck has been resting on the lake bed for quite some time, as corrosion would take hundreds of years to occur. Eventually, the ship may lose its structure when all the nails disintegrate, she said.
In the stern section of the vessel, there are indications of a central rudder, a feature used for steering, which normally did not appear before the late 13th century. Combining those two features, archaeologists were able to estimate the range of the ships no earlier than 1300 and no later than 1850.
The ship appears to have been built using a Nordic technique, in which the body planks overlap each other. This method was used during the Viking Age as a way to make the craft lighter and stronger and is known as clinker construction.
Since the wreck was found in the middle of the lake, Ødegård believed that the ship had sunk in bad weather. The ship most likely used square-shaped sails, he added, which proved difficult to navigate for seafarers caught in windy conditions.
The oldest ship discovered in Norwegian waters to date is the Sørum wooden boat, found at Bingen Booms on the Glomma river and dating from 170 BC.. The nearly 2,200-year-old shipwreck was relatively well preserved for being thousands of years old.
“Wooden shipwrecks can be preserved very well in freshwater, as they lack the organisms that normally eat wood found, for example, in the ocean,” Ødegård said. “I suppose if we are going to find intact medieval or Iron Age vehicles in Norway, then (Lake Mjøsa) would be the place to look, as it is large enough to have had its own distinct maritime history with much shipping and trade. . . ”
During the Viking Age, the lake served as a great trade route, although there are notable gaps in what is known before and during these times, according to Ødegård. “No matter the age, any find will help us better understand how the shipbuilding tradition on an inland lake developed, compared to the Nordic countries.”
To map the bottom of the lake, the research team used a State-of-the-art autonomous underwater vehicle called Hugin, from Norwegian technology company Kongsberg Maritime. This is the first time such equipment has been used in a freshwater environment, according to Ødegård, and it hasn’t seen much use in archaeology. He called Hugin’s research request for this occasion a “rare gift.”
On the last day of the exploration, the researchers sent out an ROV in an attempt to capture images of the wreck, but had to abort the mission due to bad weather. Ødegård intends to come back next year to try again.
Meanwhile, the researchers continue to map the bottom of the lake. To date, they have only mapped 15 square miles (39 square kilometers) and have much more to do. Ødegård said that he anticipated that more shipwrecks would be discovered.
“We were able to find boats from the beginning of human activity in the area. They could be present and in good condition,” Ødegård said. “Nothing can be ruled out.”
