Operation Overlord
Once the beaches had been controlled, the Mulberry Harbours were set up around 9 June. One was constructed at Arromanches by British forces and the other at Omaha Beach by American forces. Severe storms on 19 June caused problems with the landing of supplies and destroyed the Omaha harbour. The Arromanches harbour supplied around 9,000 tons daily until the end of August 1944, when the port of Cherbourg had been captured by the Allies.