Empire ship the Normandy invasion depended on the successful construction of the Mulberry ports. These were prefabricated ports, constructed at Southampton, Gosport, Portsmouth, Tilbury Docks, and even as far north as Birkenhead and Hartlepool. Two hundred tugs then took three months to tow the components of the harbours from where they were constructed to assembly areas on the South Coast. Between 7 June 1944 and the end of July, the tugs towed the materials across the channel to Normandy. Before D-Day, sixty old merchant ships and four old warships were selected as blockships, to be scuttled in a line to give protection
Race to the Sea French Territorial divisions from Lens to Lille and on 5 October, Marwitz ordered the cavalry to advance westwards to Abbeville on the Channel coast and cut the railways leading south. At the end of 6 October, Falkenhayn terminated attempts by the 2nd Army to break through in Picardy. To the north, the I and II Cavalry corps attacked between Lens and Lille and were quickly forced back behind the Lorette Spur. Next day, the cavalry was attacked by the first troops of the French XXI Corps to arrive as they advanced eastwards from Béthune. The German 6th Army took Lille