An aerial photograph of the Mulberry Harbor off Arromanches, France. Artificial harbors were constructed along the beach shortly after D-Day so that armored vehicles and heavy guns could land. (U.S. Army)
In June 1944, Allied forces needed a way to feed and supply the tens of thousands of men pouring across the D-Day beaches at Normandy to break Nazi Germany’s grip on Western Europe.
The Germans held nearby cities, and the Allies lacked a port where ships could unload. So the invasion planners decided to build their own.
“The Germans knew that ports were vital to any allied success,” historian Peter Caddick-Adams wrote in his 2019 book about the invasion, “Sand & Steel.”
“They never conceived their opponents might bring their own with them,” he wrote.
They were called Mulberry harbors, and President Biden’s plan to build a temporary harbor and pier to supply food to starving people in Gaza, announced Thursday, recalls the historic project at Normandy that helped end World War II.
As the invasion began on June 6, 1944, thousands of U.S., British and Canadian soldiers, and tons of materiel, came ashore via the landing beaches.
But Allied commanders feared that bringing men and supplies to the beaches in smaller vessels might not sustain the necessary flow of soldiers and goods into Nazi-occupied France. Deeper-water ports were needed where larger ships carrying more cargo could unload.
The British built two, according to Britain’s Institution of Civil Engineers. One was a success. The other became a disaster.
Mulberry A was constructed for the Americans off Normandy’s Omaha Beach to supply U.S. forces, the Institution of Civil Engineers says on its website.
Mulberry B was built off Gold Beach at Arromanches to supply British and Canadian troops.
The structures were essentially offshore crescents of sunken ships, floating breakwaters and giant, sunken, 7,000-ton concrete caissons designed to provide a calm anchorage where ships could unload. There were also docks and steel roadways floating on pontoons.
The components were built in Britain and towed across the English Channel by tugboats. Some of the caissons were swamped, and the crews on board guarding them were drowned, Caddick-Adams wrote.
The harbors were ready within 12 days after the landing, the Institution of Civil Engineers says.
“The whole project was majestic,” British Prime Minister Winston S. Churchill, who had championed the idea, wrote later in his World War II memoirs. “Deep-draught ships could lie at anchor and discharge, and all types of landing craft could ply freely to and from the beaches.”
Mulberry B was a success. In the 10 months after D-Day, it was used to land more than 2.5 million troops, 500,000 vehicles and 4 million tons of supplies.
Mulberry A was initially a success, too. The first ship to use it on June 16 unloaded 78 tanks and trucks, Caddick-Adams wrote. Twenty-six thousand tons of materiel was unloaded over the next three days.
But disaster hit on June 19. A violent storm struck the Normandy coast, damaging Mulberry B and wrecking Mulberry A. Mulberry B continued to operate. Mulberry A was abandoned.
“The US Mulberry has been all but forgotten,” Caddick-Adams wrote. A bronze plaque near an American cemetery in Normandy commemorates it, and a small concrete remnant survives as part of a local pier.
