The constables tower, located on the south western side of the outer curtain at Dover Castle was constructed in the 1220s to replace the northern gateway. It originally consisted of a D shaped tower which was constructed during the reign of King John (1199-1216) but was modified after the siege of 1216 to form a heavily fortified gateway which was protected by the outer moat and a drawbridge which linked with a stone causeway. In addition to its function as a fortified gate, it was also the official residence of the General Commanding Officer/Deputy Constable it has had a domestic and ceremonial function for many years.

The 13th-century additions post-siege consisted of wrapping the central D-shaped tower between two flanking towers of unequal size at the rear and a forward gate tower, all finished by 1227. The major additions and rebuilding were undertaken in 1883-4 by Colonel, later General, Robert Nicholl Dawson- Scott, R.E. (the framed as-completed elevations are dated 1886), which added a modern Gothic house and garden on the south side of the gate, and a service wing on the north. Despite the later modifications to the tower and residence there are very substantial medieval remains. In sum, the medieval arrangements provided a central hall with superimposed chamber over the gate passage, a pair of smaller chambers on the south side and two larger ones (with garderobes) on the north. Stone arches and some of the vaulting appears authentic, though the hall is heavily restored and has a Tudor fireplace; the second floor windows on the east side are presumably all Victorian. The Games Room may have medieval timbers in the ceiling. (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 English Heritage, 2014, Dover Castle Conservation Management Plan Volume 2 Gazetteer (Unpublished document).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.