The site is a scheduled ancient monument located on a hillside facing roughly South East. The site is listed because it contains the remains of a timber mote & bailey castle.
There are a number of earthworks and dry moats on the site most of which are believed to be mediaeval and associated with the castle. A number though seem to line up exactly with the WWI works shown on the map ARA48 attached, there is what appears to be a section of a, largely filled in, fire trench running from the church boundary wall along the line shown on the map ARA48 attached, between grid ref 584699-161648 and grid ref 584645-161596, to just before where the trench should curve around the ditch, also shown in the map, approximatly 75 meters in length with one or two short gaps. Near the churchyard wall are what seem to be the visible remains of two fire bays.
Mounds or bumps in the ground which seem to be in the positions of two of the MGE's were noted at grid references 584634-161605 and 584580-161618. Other irregularities in ground levels were noted at grid references 584565-161622 and 584644-161623 on the positions indicated on the map ARA48 as the location of the two shelters on the site.
All the above will need archaeological investigation to confirm these observations.
The owner Mr Goldfinch also indicated that some believed the site Roman, as indicated in the old photographs. (1)

<1> Kent County Council, 2013-2017, Defence of Swale Recording Form (Unpublished document). SKE32091.