Shallow seas are influenced by a magnitude of processes, acting on- and offshore. Therefore, most inner continental shelf areas have a unique appearance. Sediments and morphological features preserve information both about the geologic history and recent processes. In this study, extensive hydroacoustic surveys, including side scan sonar, multibeam echo sounder, and reflection seismic measurements, as well as sedimentological analyses were carried out in the Fehmarn Belt (SW Baltic Sea, Germany) and offshore Khao Lak (Andaman Sea, Thailand) between 2007 and 2011. The geologic evolution of a drowned river system since the last glacial as well as recent sediment dynamics of a subaqueous dune field were investigated in Fehmarn Belt. Offshore Khao Lak, the impact of the 2004 Indian Ocean Tsunami was evaluated.