Posted on July 13, 2026
Giant concrete structures floated across the English Channel, were sunk off the French coast, and helped create an artificial harbor used to move men, vehicles, and supplies in one of the largest logistical operations ever conducted at sea.
The United Kingdom built, floated, towed, and sank at sea enormous concrete caissons to form one of the most impressive artificial harbors ever used in a military operation, a solution created to transform an open coast into a continuous supply point.
To make this operation possible, prefabricated parts were built in Great Britain, transported by tugs, and positioned on the French coast, where some of them were sunk in a controlled manner to create a zone protected from the waves.
Mulberry Harbors took a ready-made structure across the English Channel
According to the Imperial War Museums, the Mulberry Harbors arose from the need to supply troops landed on open beaches, without relying on the immediate capture of a French port capable of sustaining the flow of men, vehicles, and cargo.
