Evolution of the Palaeolithic landscape at the westernmost tip of continental Europe: The shoreline seen by the Menez Dregan dwellers

The successive dwellers of the Palaeolithic Menez Dregan site (Finistère, France) experienced a different landscape because of the relative sea level transgressions and regressions which affected Audierne Bay between 465 and 369 Ka. We computed a series of bathymetric measurements and then produced a series of 3D images between Penmarc'h Bill, the Sein Ridge and the –120 m isobath to reconstruct these landscapes. Due to the lack of flint in the onshore and offshore Brittany basement, the –40 and –80 m regressive stages have been particularly well studied as they correspond to two well-developed flint-rich boulder bars. The other topographic features which probably attracted the attention of pre-Neanderthals were: (1) the vertical granite cliffs of Sein, Audierne and Penmarc'h; (2) the mid-Bay granitic pinnacles and cascade; (3) the Raz pass, which was the only communication route between the Audierne and Douarnenez Bays; (4) the Goayen and Pouldreuzic Rivers; (5) the Ar Palinier plateau made up of shelly limestone characterised by small caves and dolinas; (6) the Bigorne marsh, infilled by continental mud, which received drainage from all the rivers and the cascade; (7) the gentle south-facing slope located south of Sein island and (8) the N130° 2 m linear step cutting across all of their territory. Some of these data suggest that other Palaeolithic sites may have occurred at a deeper depth than the present sea level.