Water levels in the Baltic Sea have fluctuated  since the Last Glacial, and coastlines have been at locations where water depth today is meters. We want to understand these  changes and reconstruct prior lake boundaries and  river channels in Mecklenburg Bay in the German Baltic Sea. This was done with acoustic remote sensing, video observation, and sampling and dating of seafloor sediments. Knowing the paleogeography is important for locating flooded sites of archeological interest.