Pas-de-Calais Defences in the Second World War

As of June 1944, the Pas de Calais sector was the most heavily fortified area on the Atlantic Wall, and most of the Wehrmacht's mobile panzer divisions were clustered around this facility. German engineers constructed 440 obstacles per mile in the Pas de Calais area, which represented the highest density of Atlantic Wall defenses anywhere in Europe. This came at the expense of Normandy, which only had 138 obstacles per mile. By D-Day, 400,000 more mines had been laid in the Pas de Calais area compared to Normandy. The Führer, sole decision-maker in the German High Command, believed this is where the Allies would focus their main invasion efforts.