Aquitaine " water country ". It is the pitchfork of the French prehistory. The Earth of addition of the men and the cultures, this oceanic region with varied landscapes, extends the central Clump mountains in Pyrenees, separating the Iberian peninsula. Its physical geography associates three structural authorities: in the North-East, a fragment of the central Clump; in the South, the western part of the pyrenean chain and to its front the country. Among both, the western half and the North-East, it opens a triangle on The Biscay Bay constituting the most important part of a region on the exchangeable stations.