Along the whole of St Ouen’s Bay, the Germans constructed defensive positions to prevent landings on the beach, as well as creating “killing fields” to the rear across the flat dune area in the event that the Allied managed to get past the coastal bunkers without either destroying or capturing them.

Massive concrete anti-tank walls were constructed along most of the bay and older Napoleonic era forts were adapted and strengthened to supplement the new bunkers. Ironically, after D-Day in 1944 and the Allies had liberated France, the direction of the threatened invasion switched from west to the east, and some of guns were hastily moved to additional eastern defensive positions facing France.