Living at the margin of the retreating Fennoscandian Ice Sheet: the early Mesolithic sites at Aareavaara, northernmost Sweden

During an archaeological survey in Pajala parish, northernmost Sweden, clusters of quartz waste from knapping and burnt bone were discovered on a glaciofluvial gravel plateau close to Aareavaara village in the Muonio River valley. Sampled materials from a larger area and small-scale excavations (in total 6 m2) are interpreted as resulting from short-stay hunter-gatherer camps. Radiocarbon dating on burnt bones suggest an age of occupancy at ~10,700 cal. yr BP, which is more or less contemporary with 'Komsa Phase' sites on the north coast of Norway (~300-360 km northwards). The Aareavaara site should thus be the oldest known archaeological site to date in northern Sweden. A palaeoenvironmental reconstruction, based on pollen analysis of sediment cores from two nearby lakes and radiocarbon dating of macrofossils for construction of time/depth sedimentation curves, suggests a deglaciation age of the area corresponding to occupation by early man (~10,700 cal. yr BP). Aareavaara was at the time of deglaciation situated in a transitional zone between subaqueous and subaerial ice-margin retreat from the northeast towards the southwest, with higher hills and plateaux forming an archipelago in the Ancylus Lake with highest shorelines formed at ~170 m a.s.l. The hunter-gatherer camp sites at Aareavaara were thus, both in time and space, located in close proximity to the retreating ice sheet margin, but also in a waterfront location, in fact on an island in the Ancylus Lake. Our pollen data suggest a subarctic birch woodland tundra landscape characterized by open vegetation, including occasional birch trees and an abundance of willow and dwarf birch.