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Reconstructions of ice cover during the time spanning the Late Weichselian maximum show a confluent Eurasian ice sheet with the Scandinavian Ice Sheet positioned between the Svalbard-Barents-Kara and the British-Irish ice sheets. It has long been suspected among glacial geologists that the maximum ice-marginal position was asynchronous, but only recently has it been possible to explore this in some detail. Dates pertaining to the ice margin of the Scandinavian Ice Sheet reveal an old (29-25 ka) maximum position along its western flank, whereas a younger (18-16 ka) maximum position has been delineated along its eastern flank. A time -distance diagram across the Scandinavian Ice sheet shows an oscillatory western ice front, as opposed to a steadily growing and decaying eastern ice margin. The largest age difference between maximum positions is as much as 10 ka between different sectors of the Scandinavian Ice Sheet. Older maximum positions of the western margin can be explained by its proximity to icegrowth centres, initial windward ice growth, efficient ice drainage in ice streams on the Norwegian continental shelf, and the continental shelf break being a barrier to further westward expansion. Younger maximum positions of the eastern margin can be explained by a very long distance between ice-growth centres and marginal positions, slow flow in a wide zone of cold-based to partly cold-based ice, and punctuated advances of low-gradient ice lobes into proglacial lakes along the extreme eastern perimeter of the ice sheet. The influence of these lakes on the glacier dynamics of adjoining ice lobes prolonged the ice sheet advance by some 1 to 3 ka compared with adjacent interlobate areas.

We examine three questions concerning the post-glacial geological history of the eastern Gulf of Finland: (1) the amplitude of the Holocene sea-level regressions; (2) the time and mechanism of the development of large sand accretion forms (bars and spits), including dunes; and (3) the sea-level changes and coastal development over the last 4 kyr. Recent on-land geoarchaeological studies, as well as detailed marine geological research of the Gulf of Finland nearshore bottom, have provided new data for developing a hypothesis about the palaeogeographical development of the area. Geoarchaeological studies carried out around Sestroretsky Artificial Lake and within Okhta Cape, as well as analyses of previous studies of the Neolithic–Early Metal settlements, have shed new light on some aspects of coastal system development. Geographical information system (GIS)-based modelling of Holocene shorelines for the different time periods can be useful for future archaeological research. A series of submarine terraces was found at the bottom of the Gulf (sea depths from 10 to 2 m). The analysis of marine geological data (submarine terraces) and distribution of archaeological sites can be explained by a possible rise in relative sea level in the Gulf of Finland at 5 ka BP and a regression around 3 ka BP.