A series of long thin linear features can be seen on aerial photographs taken in 2007. These are situated on the mud bank north-west of St. Mary's Bay. Up to six lines can be identified which with one exception are between c.700m and c.800m in length. These are first seen on aerial photographs taken in 1955 and can also be seen on air photos taken in 1973. It is possible that these may be the remains of the Second World War boom that crossed the Thames from St. Marys Bay to Canvey Island. This site was mapped from aerial photographs as part of the English Heritage: Hoo Peninsula Landscape Project.