Prior to the invasion of Normandy in June 1944, Lepe was used as a secret manufacturing site. Six massive concrete caissons (type B2 Phoenix breakwaters) were built here and later towed across the English Channel where they formed part of the artificial Mulberry harbours after D-Day.

Lepe was also one of the many places on the south coast of England used for the embarkation of troops and equipment for the invasion. Concrete mats like big chocolate blocks were used to reinforce the shingle beach for heavy traffic.

Some of these mats can still be seen today along with pier remnants, bollards and various concrete and brick structures. Lepe was also the point where PLUTO (Pipeline Under The Ocean) left the mainland.

It carried fuel across the Isle of Wight and under the English Channel to the Allied forces in Normandy and beyond.