An archaeological watching brief carried out in 2003 found a 18th century well or cess pit cut through the fill of a medieval ditch. The feature comprised brickwork consisting of straight bricks criss-crossed over one another and forming small overhangs, with no mortar observed. The diameter of the feature could not be ascertained as it was difficult to observe.
The water table was identified at a depth of 3.25, and the base of the feature was identified at 3.50m, leading to interpretations that the feature may have represented either a brick-lined well or potentially a cess pit. The building within which the feature was excavated was thought to have been constructed within the infilled medieval ditch of the early Norman castle. The ditch was recut and replaced into the post-medieval period, and served for some time as an open sewer, implying the presence of running water in the area. (1)

<1> Canterbury Archaeological Trust, 2003, An Archaeological Watching Brief at 23 Dane John, Canterbury. (Unpublished document). SKE55058.