The Atlantic wall was a shambles as Rommel found out to his disgust after he took Command, they can't have used too many resources on it before 1944? they hardly strengthened it at all until early 1944, (just a few months before D-DAY) when Rommel took command.
Hitler ordered the construction of the fortifications in 1942. Almost a million French workers were drafted to build it. The wall was frequently mentioned in Nazi propaganda, where its size and strength were usually exaggerated. The fortifications included colossal coastal guns, batteries, mortars, and artillery, and thousands of German troops were stationed in its defences.[a] When the Allies eventually invaded the Normandy beaches in 1944, most of the defenses were stormed within hours. Today, ruins of the wall exist in all of the nations where the wall was built, although many structures have fallen into the ocean or have been demolished over the years.
Early in 1944, with an Allied invasion of Nazi-occupied Europe becoming ever more likely, Field Marshal Erwin Rommel was assigned to improve the wall's defences.[5][8] Believing the existing coastal fortifications to be entirely inadequate, he immediately began strengthening them.[8] Rommel's main concern was Allied air power. He had seen it first-hand when fighting the British and Americans in North Africa, and it had left a profound impression on him.[8] He feared that any German counterattack would be broken up by Allied aircraft long before it could make a difference.[8] Under his direction, hundreds of reinforced concrete pillboxes were built on the beaches, or sometimes slightly inland, to house machine guns, antitank guns, and light and heavy artillery. Land mines and antitank obstacles were planted on the beaches, and underwater obstacles and naval mines were placed in waters just offshore.[9] The intent was to destroy the Allied landing craft before they could unload on the beaches.[9]