This feature is recorded as part of the English Heritage report on the Second World War Stop Line in the Hoo Peninsula. This section of the line is north and west of Buckland Farm, Cliffe. The monument record for the Stop Line section is at TQ 77 NW 1228.
The report states:" Cliffe Quarries to the south bank of the River Thames, NRHE 1418715, 1418664. The quarries for the cement works at Cliffe, were used as part of the stop line to the north and west of Buckland Farm. Eighteen anti-tank blocks of a moveable type were positioned near West Court Farm, Cliffe at TQ 724 756 (Defence of Britain Project, accessed via Archaeology Data Service) but were not seen on aerial photographs. An anti-tank ditch and other features were constructed at the western end of the stop line to bridge the gap between the quarries and the Thames estuary. This final section of the stop line was formed by widening and deepening a drainage ditch (TQ 7120 7586) for 420m from the quarry to the sea wall. Six concrete anti-tank pillars were placed across the sea wall to the River Thames. One pillar has names inscribed in concrete, 'F.C. Gomar', 'S. Bernard', 'R. Lucas', (Defence of Britain Project, accessed via Archaeology Data Service).
Condition: The anti-tank blocks at West Court Farm, identified on the ground by the Defence of Britain project, require a site visit. Recent aerial photographs (Google Earth 2013) show a large section of anti-tank ditch was quarried away but the pillbox and concrete pillars are in place." (1)

<1> historic england, 2014, Hoo Peninsula Landscape Project: Second World War Stop Line: Hoo St Werburgh to Higham Marshes. Research Report 9-2014. (Bibliographic reference). SKE31599.