The earthwork remains of three adjacent irregular mounds thought to be medieval saltern mounds were seen centred as a group at TQ 7382 7725 adjacent to a small watercourse or drain. The individual mounds were located at TQ 7381 7722, TQ 7382 7726 and TQ 7385 7729 and measured 20m x 26m, 14m x 44m and 27m x 40m. An irregular embanked enclosure was also noted on the opposite side of the drain which could be a further saltern mound. This site has been recorded separately in NMR Monument Record:1532210.

These mounds are the result of large-scale salt manufacturing where brine was extracted from salt-rich sands and sediments, concentrated and evaporated using process known as sleeching. The discarded waste material from the process built up around the production area into a sizeable mound, often with a hollow in the centred where a hut stood. These medieval saltern mounds are typically described as `floriate' in form because of their irregular lobed formation of dumped waste. They often occur in clusters around former and surviving tidal water-courses within the marsh. There has been considerable reclamation and subsequent sea wall construction since the medieval period which has isolated these sites from the sea.

Roman finds have been extracted from some of these sites, but are believed to be from the lower levels, and not associated with the mounds. Post-Roman flooding and silt deposition has resulted in Roman sites lying typically several feet below the current land surface.

These have been mapped from aerial photographs as part of the English Heritage: Hoo Peninsula Landscape Project. (1-4)

<1> 1946, Photograph (Photograph (Print)). SWX9443.

<2> 1946, Photograph (Photograph (Print)). SWX9633.

<3> 1947, Photograph (Photograph (Print)). SWX9856.

<4> 1947, Photograph (Photograph (Print)). SWX9864.