Charles-Tanguy Le Roux, Former General Heritage Curator for the Regional Directorate of Cultural Affairs of Brittany and also Deputy Director of the Joint Research Unit "Atlantic civilisations and Archaeological sciences", associating the CNRS, Rennes 1 University and the French Ministry of Culture and Communications. The author has directed numerous excavations of megalithic monuments in Brittany, in particular in Gavrinis and Locmariaquer. Yvon Boelle, Photographer, constantly tours celtic lands seeking fresh images. He is the author of a number of other books from Editions Ouest-France.