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The seafloor relief of the Cabrera Archipelago National Park displays a noticeable diversity, with a pronounced asymmetry both east-west and north-south. East of the northern islets there is a wide platform bounded by the 55 m isobath, on top of which a number of cemented sandbars and sand ridges occur, together with interspersed giant sediment waves. In contrast, water depth increases rapidly westward. To the north of the archipelago depths are markedly shallower than in the south, where 100 m depth are reached at short distance from shore. The seabed southward of Great Cabrera Island shows a large field of north-south oriented deep sediment waves, i.e. normal to the local isobaths. At the southeastern corner of the Park there are some large cemented sandbars with a west-east mean orientation that seem to continue eastward, beyond the mapped area. Other outstanding submarine landforms that appear locally include a barchan dune field, mounds and bumps clusters, terraces and steps on the inner shelf, sediment tails in the straits between islets, a submarine channel following the thalweg of Es Port, the sediment infill of some small coves and bays, and even a possible submarine landslide deposit off Llebeig cape. All these elements are described and interpreted for the first time in this contribution. Some of the seafloor landforms seem to relate directly with the geological structure of Great Cabrera and the smaller islets. The submarine valley along the axis of Es Port is the best example, as it seems to be associated to a south-east to north-west oriented thrustfront that also controls the path of ses Figueres channel inshore, which is the main course of the principal subaerial watershed in the entire archipelago. The continuation of the pronounced slopes and coastal cliffs into the sea becomes also obvious in numerous places. Finally, the overall physiography and the seafloor relief, together with variations in its constitution from place to place and the action of oceanographic processes, play a key role on the composition and distribution of benthic habitats occurring across the National Park. [ABSTRACT FROM AUTHOR]