Jaana Pajarinen, a teacher from the town of Outokumpu, made the find in the early spring of last year on the island of Luutsalo in the area of Heinävesi. Dating back millennia, the ancient images were painted on a glacial boulder.
Martti Koponen, an archaeologist from the Savonlinna Provincial Museum, was the first professional to see the site, visiting this week to examine and document the find.
"The paintings apparently depict an elk and possibly another smaller elk and a stick figure of a human," explains Koponen. A more detailed technical examination is expected to provide more information about the images.
The most unusual feature of the discovery is that the position of the paintings is so close the surface level of the surrounding lake. In most parts of the country, the topography has changed radically over the centuries, with land rising and water levels falling, and leaving such Stone Age rock paintings on cliff faces high above the waters in which they were once reflected.
On the basis of the Luutsalo find, it is though likely that there may be more waiting to be discovered in the area.