The Hensbakka or Fosna culture is the oldest section of the Swedish and Norwegian Mesolithic. Some researchers see Fosna but as a maritime form of the Ahrensburg culture. Distribution: North Swedish west coast of Halland to Vättern (lake). You will probably start around 9500 and lasts until about 7000 BC The living spaces are connected to the 40-90 m shoreline. Typical artifacts are rough lanceolate microliths, disc hatchets, unipolar and bipolar blade cores with a working surface, stem tips, Høgnipen tips and Lerberg hatchets.
It is divided into four phases according to Åke Fredsjö ( 1913-1978 ). H. Kindgren recognizes only two phases, with an older stem tips before 9700 BP and a younger lanceolaten with microliths from 9700-9200. Numerous middens are known, especially in the area of Udevalla. Presumably based diet as the Askola culture mainly on seals, but there are also find sites inland known.