372. British innovations made D-Day possible. 'Mulberry' concrete & steel temporary roads enabled 2million men, half a million vehicles to land on Normanby beaches
Each Mulberry had the capacity to move 7000 tons of vehicles, men and supplies from ship to shore each day. After D-Day, two were constructed in 3 days, at Omaha (US) and Gold (UK) beachheads
A British invention, the Mulberry was a temporary bridge which allowed tanks, vehicles, materiel, hospitals, men etc to be moved into France.
Each section was built secretly in Wales using local steel and hollow-core concrete. Each Mulberry harbour pod consisted of 2-6 miles (10 km) of flexible steel roadways (code-named Whales) that floated on steel/concrete pontoons (Beetles).
The roadways terminated at pierheads (Spuds) jacked up/down on legs resting on the seafloor.
These structures were sheltered from the waves by massive sunken caissons (Phoenixes), scuttled rusted ships (Gooseberries), and a line of floating breakwaters (Bombardons).
Construction of the caissons required 330,000 cubic yards (252,000 cubic metres) of concrete, 31000 tons of steel, and 1.5 million yards (1.4 million metres) of steel roadways. All this was done in secret.
Meanwhile the Nazi army strengthened their defences at Calais
They believed the aerial photos showing British resources being readied for the attack on France. But they were inflated rubber imitations, organised after the English ambassador reported what he'd seen at Macy’s Christmas parade in New York.
Germany had limited resources
Their “Atlantic Wall” was mostly propaganda. War materials were mostly sent to the Eastern front and the war against the Soviet Union (which the Nazis were losing).
Rommel was brought in and he strengthened the German beach defences significantly, especially at Omaha Beach. This made things more difficult for the Eisenhower-led Allies — but it was too little too late. The rest is history.
Report #372.
.