
The rocks of the Pène, which shelter the Castillon Towers, belong to the narrow chain of "Hills" extending for 15 km from west to east, in the Alpilles massif. Traveling Fontvieille, Paradou, Maussane-les-Alpilles and Mouriès, it ends at the Caisses de Jean-Jean. The rocks of the Pène peak at 58 meters altitude south of Paradou. They have a marked southward slope and consist of calcareous beds of the Upper Cretaceous.