Archaeology and Astronomy : Similarities and differences between Corsica, Balearic Islands and Sardiania

We present in this paper a comparative study of astronomical orientations of megalithic monuments belonging to some of the main islands of the Mediterranean basin : Corsica, Sardinia and the Balearic Islands. This comparison is based upon three kinds of analysis criteria : (i) the type of monuments which can be found in the these islands; (ii) the orientations customs established for each island; (iii) the exhibition of similarities and difference in astronomical interpretation between the islands. After a general introduction to archaeoastronomy, we give in this paper a detailed description of both the sites and the orientations measurements ; we finally proposed a comparison of orientations of the monuments between the islands.