Mulberry harbour

Mulberry harbours were temporary portable harbours developed by the British during World War II to facilitate the rapid offloading of cargo onto beaches during the Allied invasion of Normandy in June 1944. After the Allies successfully held beachheads following D-Day, two prefabricated harbours were taken in sections across the English Channel from Britain with the invading army and assembled off Omaha (Mulberry "A") and Gold Beach (Mulberry "B").

The Mulberry harbours were to be used until the Allies could capture a French port, initially thought to be around three months. However, it was not until six months after D-Day that the Belgian port of Antwerp was captured that use of the harbour at Gold Beach lessened. It was used for 10 months after D-Day and over 2.5 million men, 500,000 vehicles, and 4 million tonnes of supplies were landed using it before it was fully decommissioned. The Mulberry harbour at Omaha Beach had been severely damaged in a storm in late June 1944 and was abandoned.

The Dieppe Raid of 1942 had shown that the Allies could not rely on being able to penetrate the Atlantic Wall to capture a port on the north French coast. The problem was that large ocean-going ships of the type needed to transport heavy and bulky cargoes and stores needed sufficient depth of water under their keels, together with dockside cranes, to off-load their cargo and this was not available except at the already heavily-defended French harbours. Thus, the Mulberries were created to provide the port facilities necessary to offload the thousands of men and vehicles, and tons of supplies necessary to sustain Operation Overlord and the Battle of Normandy. The harbours were made up of all the elements one would expect of any harbour: breakwater, piers, roadways etc.

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