The Merville Gun Battery is a decommissioned coastal fortification in Normandy, France, which was built as part of the Germans' Atlantic Wall to defend continental Europe from Allied invasion.It was a particularly heavily fortified position and one of the first places to be attacked by Allied forces during the Normandy Landings commonly known as D-Day.A British force under the command of Lieutenant Colonel Terence Otway succeeded in capturing this position, suffering heavy casualties.The Merville Battery is composed of four 6-foot-thick (1.8 m) steel-reinforced concrete gun casemates, built by the Todt Organisation.During a visit on 6 March 1944, to inspect the defences, Field Marshal Erwin Rommel ordered the builders to work faster, and by May 1944, the last two casemates were completed.