The castle stands on the end of a high and narrow ridge of the South Downs, above the town of Arundel. It consists of an oblong ward, covering 4-1/2 acres, in the middle of which, but on the line of the west wall, is a large motte, about 70 feet high, surrounded by its own ditch. The lower and perhaps original bailey is only 2 acres in extent. Round the top of the motte is a slightly oval wall, of the kind called by Mr Clark a shell keep. We have elsewhere expressed our doubts of the correctness of this term.[255] In all the more important castles we find that the keep on top of the motte has a small ward attached to it, and Arundel is no exception to this rule; it has the remains of a tower, as well as the wall round the motte. The tower is a small one, but it is large enough for the king's chamber in times which were not extravagant in domestic architecture. It is probable that this tower, and the stone wall round the motte are the work of Henry II., as he spent nearly 340_l._ on this castle between the years 1170 and 1187. His work consisted chiefly of a wall, a king's chamber, a chapel, and a tower.[256] The wall of the motte corresponds in style to the work of the middle of his reign; it is built of flints, but cased with Caen stone brought from Normandy, and has Norman buttresses. The original Norman doorway on the south side (now walled up) has the chevron moulding, which shows that it is not earlier than the 12th century. The tower, which we may assume to be the tower of Henry II.'s records, has a round arched entrance, and contains a chapel and a chamber (now ruined) besides a well chamber. There is earlier Norman work still remaining in the bailey, namely, the fine gateway, which though of plain and severe Norman, is larger and loftier than the early work of that style, and of superior masonry.[257] The one Pipe Roll of Henry I. which we possess shows that he spent 78_l._ 6_s._ 2_d._ on the castle in 1130, and possibly this refers to this gatehouse.[258] We know that Henry was a great builder, but so was the former owner of this castle, Robert Belesme, son of Roger de Montgomeri. The value of the town of Arundel had greatly increased since the Conquest, at the time of the Domesday Survey.[259]