Storstrømmen is a narrow sound, separating the islands of Zealand and Falster in Southern Denmark. The area has been subject to archaeological surveys and investigations since the 1980's. In 2015, prior to the construction of a new bridge, sub-bottom data from the bridge corridor and other affected areas, were used to give a representation of the moraine till as a proxy for the submerged prehistoric topography. During the investigations, a new Paleolithic and several Mesolithic sites were found. The sites are preserved at different depths in the channel. The oldest site dates to the Federmesser Culture (12,000-11,500 BC) and is located at c. 13 m below present sea level along a prehistoric lake shore, on the former valley floor. The youngest site is located at a former coastal lagoon, only c. 1 m below present sea level and dates to the Ertebølle Culture (5400-3900 BC). Different environmental analyses are planned to investigate the changing environment of the area. The elevation and temporal distribution of sites in the area have the potential of contributing to the understanding of the environmental change of the area as a whole. Of special interest is the Holocene sea-level rise, as the rate and timing of the transgression in the area is still not well dated.