The lake has two islands, Spiginas and Duonkalnis, which have yielded Mesolithic and Neolithic burials including the Mesolithic grave of the "Duonkalnis shaman".

[1] The grave pits were shallow and filled with red ochre, and yielded grave goods of perforated pendants of elk and boar teeth.

[2] The island site of Duonkalnis (also Donkalnis) has yielded around 14 graves.

[4] His body was adorned with 57 amulets including moose teeth strung across his head and wild boar tusks on each of his eyes.

[4] The body is now on display in the Archaeology section of the National Museum of Lithuania in Vilnius.