The petroglyph was discovered by retired geologist Ingvar Lindahl at Efjorden in the Nordland county, reports broadcaster NRK.
Analysis has now estimated the petroglyph, which depicts a boat, to be between 10,000 and 11,000 years old, according to the report.
“This is an extremely important development, a global sensation in fact, and will enter the history of research in a very, very big way,” archaeologist Jan Magne Gjerde of Tromsø University told NRK.
The petroglyph was dated using estimates of the height of the water level against the rock on which it is carved, Gjerde said. Water levels in the region were higher during the Stone Age than they are today.
“The boat is a little over four metres long. You can see the keel line and the railing line, and as you move forward you can see a really beautiful finish, forming the boat's bows,” Gjerde told NRK, adding that the find was “incredibly exciting”.
The petroglyph is possibly the oldest in the world depicting a boat, the archaeologist told NRK.
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