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Along parts of the Hanö Bay coast in south-eastern Sweden, remains of a submerged landscape can be found down to depths of almost 25 m b.s.l. The coastal landscape was formed during two periods of lowered water levels in the Baltic Basin: the Yoldia Sea and the Initial Littorina Sea stages. In order to reconstruct the local environment and shoreline displacement during the Yoldia Sea and Ancylus Lake stages, sediment sequences were obtained at 4.5, 17.5 and 18.7 m b.s.l. Detailed bathymetric mapping was based on multi-beam echo-sounding while surveillance and sampling of tree remains and archaeological findings were performed through diving. The Yoldia Sea low-stand reached its minimum level at 24–25 m b.s.l. just before 10,800 cal. BP. During the subsequent Ancylus transgression, a slow-flowing river passed through the area, accumulating thick deposits of fine-grained organic sediments in lagoonal basins. The river was surrounded by open woodland dominated by pine. Based on successive flooding of rooted tree stumps, the transgression rate was estimated at 4 cm·yr−1, until the Ancylus high-stand was reached at 5 m b.s.l. at 10,400–10,300 cal. BP. Findings of worked aurochs and beaver bones provide evidence of human presence in the landscape and show the importance of terrestrial resources for their subsistence. These integrated palaeoecological and archaeological investigations demonstrate the importance of submerged landscapes with well-preserved sediment, wood and bone material for our understanding of southern Baltic coastal landscapes and their inhabitants during the Early Mesolithic.

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We present evidence of a submerged early Holocene landscape off the Blekinge coastline in the Baltic Sea, dating to the Yoldia Sea and Initial Littorina Sea Stages when the water level was lower than at present. 14C dated wood remains obtained by surveillance diving and new archaeological findings in combination with bathymetric analyses and interpolations between other sites across the Baltic Sea were used for refinement of the shoreline displacement history of the region. The new results reveal a Yoldia Sea lowstand level at 20 m b.s.l., a subsequent Ancylus Lake highstand at 3 m a.s.l., and then a period of relatively stable water level at about 4 m b.s.l. during the Initial Littorina Sea Stage, several metres lower than previously concluded. The refined shoreline displacement record was used for palaeo‐reconstructions of the study area during four key periods, the Yoldia Sea lowstand phase, the Ancylus Lake transgression phase, the Ancylus Lake highstand phase and the Initial Littorina Sea lowstand phase, using elevation data and map algebra functions. A flow accumulation algorithm was used for reconstruction of the now submerged prehistoric river network in order to identify areas of high archaeological potential. Our revised shoreline displacement record, and especially its lowstand period during the Initial Littorina Sea Stage around 9500–8500 cal. a BP, raises future demands not only for specific archaeological shallow‐water surveys down to 4 m b.s.l. in the area, but also for a renewed cultural heritage management strategy. The results of this study fill an important gap in the early Holocene part of the shoreline displacement history of Blekinge, contributing to its completion since the deglaciation, which is unique for the Baltic Sea.