East of the U.S. landing sites of Utah and Omaha beaches lies the small French village of Arromanches. If you’re not a World War II history buff, it’s role in the war may not be familiar to you. It wasn’t for me until I visited the coastline recently. Looking back, it is perhaps the most important beach in the Allied landing in Normandy in 1944 and critical for supporting the war against Hitler.

Arromanches is the site of the artificial harbor that the British built to funnel machinery and fuel to troops Allied troops in France. As in modern wars and conflicts, the flow of resources can be a strategic vulnerability.

In planning the invasion of Normandy, Winston Churchill understood without a reliable harbor, the flow of vital resources would not make it to the troops and the invasion would stall. From this harbor goods like foodstuffs, tanks, artillery, ammunition, and fuel would be delivered to the frontlines.

Established ports were heavily defended by German troops, rendering them useless for the invasion. Churchill came up with an ingenious solution: he would build all the components needed for a harbor in England and tow them across the Channel where they would be assembled in Arromanches.

You can still see remains of the large concrete structures that formed the breakwater and there is a section of the steel causeway on display. It’s a tremendous feat of engineering.

There were over a dozen ships that were sunk to provide the first relief against the swells of the English Channel, followed by a ring of reinforced concrete shells that would fill with water and sink to the bottom of the water providing a second breakwater. Floating piers that could rise and fall with the tide provided a docking station for larger transport ships. Three causeways composed of steel sections connected the piers to the beach.

I found a quick video that shows the different components used in the artificial harbor.