THURNHAM, called also, from the hill on which it stands, “Godard’s,” Castle, near Maidstone, is a curious example of a Norman castle placed upon what is evidently a British camp.
The camp crowned the high point of a very steep spur, which juts out between a depression on the one side and a small deep combe on the other, in the great escarpment of the lower chalk, about four miles east-north-east of Maidstone. The earthworks were formed by scarping the central knoll, and perhaps raising it a very little, so as to form a slight mound, and thus especially strengthening its weak sides, those towards the root of the spur. On the lower or Thurnham front the defences, naturally strong, are reinforced by a ditch and bank, placed some little way down the hill, far below the body of the fortress, and intended to command the road which here winds up the ridge from the village and church of Thurnham, at the foot of the hill. The ground within this outer defence has been extensively opened for chalk, and is so disfigured by heaps of quarry rubbish that but little can be accurately ascertained of its ancient dispositions.
The Norman castle occupied a platform close west of the mound, and probably included within the British camp. Here stand the remains of the gateway and court, but as a trace of masonry is still seen upon the mound, it may be that it was included in the enceinte wall, or that upon it stood one of the circular or polygonal shell keeps which sometimes, with the Normans, took the place of the ordinary square keep, especially where there was an earlier mound to be fortified.
The ruins are not considerable. They are composed of the two parallel walls of a gatehouse, having on either hand two large round-headed recesses, dividing the passage into two bays, and there are besides two small lodge doors, also round-headed, on the east side.
Westwards from the gatehouse runs a low curtain wall, about 13 feet high, and 4 feet thick, for about 80 feet, ending in a broad flat buttress, perhaps the base of a square tower. The wall thence may be traced southwards, along the edge of the steep, whence it seems to have been continued towards the mound. A hollow way, cut in the chalk, winds from below, beneath and close to the west of this wall, and, making a bend, enters the gatehouse from the north. There are no traces of ashlar. Much of the wall shows a face of coursed flints. The work may be late Norman.
On the summit of the knoll is a depression in the soil. This part of the work is so covered with thick bramble and underwood that it cannot be very accurately examined.
Thurnham or Turnham occurs in Domesday, and was one of the numerous manors given by the Conqueror to Bishop Odo, and held under him at the survey by Ralph Curbespine. It then contained a church, and had been held under the Confessor by Sbern Biga.
On Odo’s fall, 19 W. C., it was granted to Gilbert Maminot by the tenure of castle guard under Dover Castle. The holders under Maminot were a knightly family, who took their name from the place. Robert de Turnham held it temp. Henry II., and founded Combwell Priory. Possibly he built the castle. Robert had Robert, who died s.p. 13 John; and Stephen, who died also s.p. 16 John.
In the reign of Edward I., Thurnham was held by Sir Roger de Northwode, who died 13 Edward I., leaving John, who married Joan de Badlesmere, and died 14 Edward II. Their son John died before his father, leaving Roger, who had Thurnham, and married Juliana, daughter of Geoffrey de Say, chief lord of the manor. Their son, Sir John, third baron, died 2 Richard II.; and his son, Roger de Northwode, who was never summoned to Parliament, alienated Thurnham, and died s.p., leaving a brother.
The Northwodes are said to have resided here, but the castle is thought to have been dismantled at an early period. Thurnham Castle is not named in the Ordnance map.