The ditch and counterscarp on the southern and western side of the outer defences at Dover Castle are mainly the result of an extensive programme of redevelopment of the outer defences which was undertaken in the 18th century (1750-1805), though some of this work involved the remodelling of the pre existing medieval defences.

The defences along the western side of the castle comprise a simple sloped earth ditch immediately outside the curtain wall which was formed in the medieval period but deepened in the Napoleonic period modifications. Beyond this is a further deep scarp and small ditch which provides protection for the spur road from town. The main ditch has banked earth sides, with chalk rock face showing at the base, and there is an outer counterscarp and gradual formation of an outer ditch towards the north end (which seems to have provided a covered way between the two castle gates). Summarised from sources (1-2)

<1> English Heritage, 2014, Dover Castle Conservation Management Plan Volume 2 Gazetteer (Unpublished document). SKE52105.

<2> Johnathan Coad, 1995, English Heritage Book of Dover Castle and the Defences of Dover (Monograph). SKE52106.