The largest remaining Allied-built structure in Normandy, the Mulberry Harbour off the coast of Arromanches and Asnelles is unmissable – not only due to its sheer size and visibility but also as an historic object all visitors to the area must go and see.
Constructed and tested at numerous sights around Britain, these huge concrete creations were floated/towed across the England Channel in the days following the D-Day landings nearly 80 years ago.
Once in location their special valves were opened and the hollow structures – known as caissons - rested on the seabed in an arrangement designed to create a huge breakwater and artificial harbour within which a series of floating roadways would be formed.
These roadways would help the Allies win the war, allowing men and materiel to be landed in huge numbers to ensure the constant resupply of troops in the weeks before a deep-water port could be captured.
There were six different sizes of caisson constructed and these can easily be seen in an almost semi-circular ring stretching from near to the shoreline west of Arromanches all the way around to Asnelles to the east.
One of the most accessible structures which also formed part of the Mulberry system lies directly on the beach at Arromanches and can be visited close up at low tide. This platform extension looks huge and was used as part of the roadway which brought ashore war materials from the supply ships docked in the protected harbour.
Nearby, and also exposed at low tide every day, there are floating pontoons known as beetles which helped to support the sections of roadway known as whale sections.
There are several of these whale ‘bridge’ section still to be found in Normandy including a six span length near the D-Day Omaha Museum at Vierville-sur-Mer, and a single section in the town centre of Arromanches.
Planning for this incredible structure began earlier in the war and in 1942 Winston Churchill raised the problem of how the piers of the future artificial harbour at Arromanches could be anchored to not only keep them in position but to help them withstand the waves and tides.
The problem was solved by Major Allan Beckett who designed the floating roadways, supporting piers, and the 'kite' anchors which enabled the harbour to work. It was a design which also enabled this vital war asset to survive the storm of June 13 to 18, 1944.
Overlooking the remains of the Mulberry harbour in Arromanches town centre, and next to a whale section and original anchor, is a memorial which honours Allan Beckett. His engineering skill made the Mulberry Harbour project a success.
Inside the newly revamped Musee du Debarquement in the town you can get an in-depth look at the full history of the harbour, its many components, and how it worked through a series of interactive displays.
An amazing piece of British engineering and planning - if you can’t capture a port… just build one!