Based on the interpretation of high-resolution seismic reflection profiles and a new 1:250,000 scale synthetic geological map, we establish that the MSC is recorded in the Corsica Basin through the occurrence of two sedimentary formations bounded by three remarkable surfaces. These seismic markers suggest local and temporal variations in relative water level and associated depositional environments that differ between the north and south of the Corsica Basin. During the MSC, the northern sector (Golo Basin) was emerged, whereas the southern sector (Orbo Basin) was often flooded or submerged. In the Orbo Basin, the deposits record both an episode of intra-MSC climate change and regional tectonic events. During the MSC, the Corsica Basin was a perched lake, isolated from the deeper Tyrrhenian basins. The connection with the Tyrrhenian basins was re-established during the final stages of the MSC, before the catastrophic Pliocene reflooding, initiated by retrogressive erosion during a relative lowstand. An extensive network of incised valleys was thus established in the Orbo basin, allowing the drainage of the Corsica Basin southwards into the deeper Tyrrhenian basins. These markers record the active regional tectonic context throughout the MSC. The Orbo basin was strongly subsident along its western rim, while its eastern rim was uplifted. In turn, the Golo basin subsided from middle Pliocene times onwards, while the northern, eastern and southern edges of the Corsica Basin were deformed and uplifted.