either of two artificial harbours designed and constructed by
the British in World War II to facilitate the unloading of supply
ships off the coast of Normandy, France, immediately following the
invasion of Europe on D-Day, June 6, 1944. One harbour, known as
Mulberry A, was constructed off Saint-Laurent at Omaha Beach in the
American sector, and the other, Mulberry B, was built off
Arromanches at Gold Beach in the British sector. Each harbour, when
fully operational, had the capacity to move 7,000 tons of vehicles
and supplies per day from ship to shore.