One of the main reasons for planning our trip to France the way we did was so that we could see several sites related to the D-Day invasion of Normandy (a.k.a. Operation Neptune). The first stop on our D-Day road trip was Arromanches-les-Bains to see what remains of the British mulberry harbor (a.k.a. Mulberry B and Port Winston).
Mulberry harbors were designed by the British during WWII. They were temporary harbors that were used to facilitate the unloading of troops and supplies — a truly brilliant feat of engineering. The mulberry harbors were designed to be able to offload enough supplies to sustain Operation Overlord for three months (the amount of time they thought it would take to capture a French port for more permanent use).
The British built Mulberry B (the Gold Beach mulberry harbor), which remained in use for ten months, at which point the Allies captured Antwerp and were able to use its port instead. Mulberry B had 10 miles of floating roadways that were used to bring both supplies and troops to shore. It took 600,000 tons of concrete to build Mulberry B. According to Wikipedia, Mulberry B was used to offload over 2.5 million men, 500,000 vehicles, and 4 million tons of supplies — the numbers definitely make it easy to see how important Mulberry B was for Operation Overlord. The Americans were responsible for building an additional mulberry harbor (a.k.a. Mulberry A) at Omaha Beach; however, it was destroyed by the storm that hit the Normandy coast on June 19, 1944.
Portions of Mulberry B can still be seen in Arromanches today. Several sections of the 10 miles of road are washed up on the beach. You can also hike up a nearby bluff to get a better view of the Phoenixes (concrete caissons) that remain there today.
Prior to arriving at Gold Beach, it never really dawned on me that the Normandy beaches are actual beaches — beaches that people swim in and play on and use for boating.