Canterbury Castle

Written by Tim Tatton-Brown, then Director of CAT, 1985

Canterbury Castle was one of the three original royal castles of Kent (the other two were at Rochester and Dover) they were all built very soon after the Battle of Hastings. They were all on the main Roman road from Dover to London, the route taken by William the Conqueror in October 1066, and it is more than likely that they were all built originally as motte-and-bailey castles in the winter of 1066–67 to guard this important route.

In Canterbury this original castle was almost certainly in the southern angle of the third century Roman city walls in the area of the present public gardens. The great mound known as the Dane John, which was landscaped to its present form in 1790, would have been the 'motte'. Dane John is a corruption of the Norman word for 'keep' – 'donjon' (a French derivative of the Latin 'dominium' signifying 'place of lordship'). The outer bailey extended northwards and part of its outer ditch was excavated in 1981 where it was to be covered by a block of new housing (see plan). Less than twenty years later the castle was moved to a new site just inside the Roman south gate (called the Worthgate), and Domesday book (1086) tells us that fourteen of the houses of tenants of St Augustine's Abbey had to be demolished for this and the King gave them the churches of St Andrew and St Mary sub castellum (i.e. the nearby St Mary de Castro church) in exchange. We also learn that eleven more houses were destroyed for the castle ditch, presumably in the area outside the City walls as Domesday book says they were in fossato civitatis.

Canterbury's motte-and-bailey castle of the mid eleventh century

Early in the twelfth century, during the reign of Henry I, the great stone keep was built. This massive structure, which has dimensions of about 98 by 85 feet externally at the base, was originally probably at least 80 feet high. It is mainly made of flint and sandstone rubble (the walls are 14½ feet thick at the base), but had quoins and a plinth of Caen and Quarr stone (from Normandy and the Isle of Wight respectively). On its north-west side was the original entrance at first-floor level and accessible by a great external staircase (only the foundations of which now exist); the keep originally had no entrances at ground level. At first floor level was the great hall, a principal chamber and the kitchen (in the south-west corner) and two very fine fireplaces still survive in the walls. Above this was a second floor which was sadly mostly demolished in 1817; it can be seen with its windows in earlier prints and drawings. The very dark basement (originally for storage only) was lit by three windows very high up in the east wall, but in the thirteenth century (probably when the Castle was already mainly used as a prison) a new large doorway and gatehouse were built on the east side. This has now been demolished, but its foundations are marked out with granite sets and the doorway into the keep (now blocked again) is still visible.

Engraving of c.1815 showing a now-destroyed crosswall

From the twelfth century at least the Castle's main use was as a prison for the County of Kent and it was under the control of the Sheriffs. Apart from the keep, there was an outer bailey (of about 4½ acres) which was enclosed by a wall and ditch and had a main gate with two drum towers facing up Castle Street into the City. On the south side, the old Roman Worthgate was still in use and as today people could pass through the bailey on their way to Wincheap. In 1548, however, this Roman gate was blocked and Castle Row/Worthgate Place was created to by-pass the Castle. This street, which went round the bailey on the east had a new gate, the Wincheap Gate, created for it in the City walls. On the north-west side of the bailey another street ran past St Mildred's churchyard and out through a postern in the City walls. These two streets came together again at the top end of Wincheap (called Wincheap Green and now covered by a roundabout) where there was a gallows which is clearly shown on the map of Canterbury c. 1640.

The Castle remained a County Gaol even after Canterbury became a County Borough in its own right in 1448 (the area of the Castle was a detached portion of the County of Kent right up to the nineteenth century). In 1730 a fine new County Sessions House was built which still survives and was probably on the site of the old Great Hall. Sadly, the eighteenth century also saw the beginning of the end of the Castle's life. By this time the keep was already a ruin and partial demolitions took place in 1770 and 1792. The later year also saw the demolition of much of the outer bailey walls and also of the Roman Worthgate to allow an improved Castle Street once again to run through the area. In 1817 much of the upper walls of the keep were pulled down, and in 1825 the newly formed Gas, Light and Coke Company bought the keep and pulled out the two internal cross walls so they could use it as a coal and coke store. An iron tank for water was also put on top of the keep, and it was only in 1928 that the keep was acquired by the City and preserved.

Tentative reconstruction of Canterbury Castle
in the early twelfth century

The Castle area from the C.A.L.C. Map 123 (c.1640)

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