A group of five or six salt-pans and a windpump are depicted on Hasted's 1782 map of the area. These were situated on the south coast of the Isle of Grain to the west of Horseshoe Point. The slight earthwork remains of narrow banks and a low irregular shaped mound 75m x 53 can be seen on aerial photographs taken in 1946 - although they do not define pans as shown on the 18th century map. These features, which were levelled during the building of the post-war BP refinery on Grain, were mapped from aerial photographs as part of the English Heritage: Hoo Peninsula Landscape Project.