Beginning 1943, Nazi Germany started to build a line of fortifications in the Pyrenees, called , from Cerbere to Hendaye, along Le Perthus, Maurellàs, Las Illas, Prats-de-Mollo-la-Preste and the French Cerdagne and built coastal batteries in Le Barcarès, Torreilles, Sainte-Marie-la-Mer, Collioure et Port-Vendres which became part of the Südwall.