Barnfield Pit was opened in the later 19th century, sometime between 1862 and 1899 as it is shown on the 2nd ED OS map, to supply gravel and then chalk to the main Swanscombe Cement works to the north-east. It formed an extension to the Claylands Pit which lay between the railway line and London Road. The main part of the quarry was backfilled in the 1950's and 1960's using Thanet Sand. (location accurate to the nearest 10m based on available information)