This site is on the east side of Sandbanks Hill at Green Street Green and originated around 1939/40. It was designated S18 and formed part of the Thames and Medway Gun Defended Area. In April 1940 it was listed as a practice camp armed with 2 old pattern 3-in. guns. It subsequently received 4 x 3.7-in. guns. Official documentation may suggest that it was disarmed from at least as early as May, 1942 but eyewitness reports affirm that this was not the case and that it continued in use for a longer period, being rearmed with heavier 4.5-in. guns and gaining two further gun emplacements. Second World War heavy anti-aircraft battery (S18) at Warrigal Farm, Green Street Green, nr Dartford. Built by 1940 with 4 (later 6 emplacements) around a command post These remain, with magazines, a battery road and traces of the domestic area. The date of decommissioning is not known but was no earlier than 1945. It is currently in use as a riding school and stable.