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The Messinian Salinity Crisis (MSC) involved the progressive isolation of the Mediterranean Sea from the Atlantic between 5.97 and 5.33 Ma, and a sea‐level fall whose timing, modalities, and magnitude remain actively debated. At that time, the central Mediterranean was undergoing strong tectonic activity due to the rollback of the Adria slab and eastward migration of the Apenninic belt. The combined effects of the post‐evaporitic MSC sea‐level drop and morphostructural changes (due to the Intra‐Messinian phase) resulted in a regional unconformity, which shows erosive markers and conformable relationships with the Messinian and Mio–Pliocene boundary in the Po Plain and Northern Adriatic Foreland. Here, we produce a palaeotopographic reconstruction of the Po Plain‐Northern Adriatic region (PPNA) during the Messinian peak desiccation event based on such regional unconformity. We mapped this surface through wells and 2D seismic data form Eni's private dataset. The unconformity shows V‐shaped incisions matching the present‐day southern Alpine valleys and filled with Messinian post‐evaporitic and Pliocene deposits, suggesting that the modern drainage network is at least of late Messinian age. The Messinian unconformity has been restored to its original state through flexural‐backstripping numerical modelling. The resulting landscape suggests a maximum sea‐level drop of 800–900 m during the MSC peak, and is consistent with stratigraphic and sedimentologic data provided by previous works. The modelled shoreline separates the subaerially eroded land from an elongated basin composed by two ca. 400 and 1,000 m deep depocentres during the maximum sea‐level drop. These results suggest that the Mediterranean was split in at least three sub‐basins subject to independent base levels, fresh‐water budgets, and flexural responses during the maximum lowstand.

The architecture of foreland basins and the resulting distribution of clastic sediments are related to the constant interplay between tectonics and sedimentation. Specifically, basin floor modifications strongly influence dimensions, continuity and connections of sand‐size and fine‐grained deposits. Given the increasing need to identify deep potential reservoir deposits, the large‐scale definition of clastic porous targets and their seals is a matter of interest for oil and gas industry. Here, we present the reconstruction of the Po Plain and Northern Adriatic Foreland Basin (with an extent of ca. 40,000 km2) and its Pliocene–Pleistocene evolution, as an example of a sedimentary clastic system controlled by strongly non‐cylindrical foreland geometry. The study is based on the basin‐scale mapping of six unconformity‐bounded sequences, performed by interpreting a dense network of seismic lines and correlating well‐log data. This provides a three‐dimensional model of the step‐by‐step evolution of the basin and a description of the sediment dispersal pattern. We found that the basin records the change from a continuous (cylindrical) to highly fragmented (non‐cylindrical) foredeep geometry during Late Pliocene. In the Northern Apennines case, the main factors driving the development of a non‐cylindrical geometry are mainly related to inherited inhomogeneity in the downgoing block linked to its Mesozoic extensional faulting, and the relative orientation of these lineaments with respect to the direction of orogen migration. During the late Pliocene–Pleistocene the two directions progressively became close to parallel, and the Northern Apennines system reacted changing from a cylindrical to a non‐cylindrical state.

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