A rectangular earthwork enclosure with a slight mound at its centre, possibly representing a gun emplacement, is visible as slight earthworks on aerial photographs and has been mapped as part of the English Heritage: Hoo Peninsula Landscape Project. The feature probably dates to the First World War, as aerial photographs taken during and just after the Second World War show very low earthworks. The site lies within an area described, on a War Department map of Lodge Hill field defences, 1914-16, as part of the "New field works ground", and is located immediately adjacent to First World War practice trenches (Monument 1546275). It coincides fairly closely with a spot labelled on the map as a blockhouse, and may represent the footings of a structure within an enclosure.