The forebuilding covering the entrance forms almost as remarkable a feature here as at Rochester or Middleham, though it has suffered much from alterations. It was a rectangular tower built against the west wall of the keep, and projecting 38 feet. Its walls are 6 feet thick, bonded into and of the date of the keep. The west wall has been in part removed down to the plinth, but the two other walls are tolerably perfect. It was of two stages and about 40 feet high. The door was in the south wall, opening from the inner ward. It may be traced, but has been in part replaced by an entrance of Perpendicular date, now also broken away. Above the old door, 12 feet from the ground, is a plain Norman string. From the door a straight stair, reversed with a second flight, must have risen 25 feet to reach the first floor. At that level, over the entrance, was a chamber, of which part of the Norman wall remains, but which was rebuilt by Dudley, and has been nearly all destroyed. Here was possibly a chapel, as at Middleham. The entrance to the first floor of the keep opens from this level, in the curtain, close to the south-west turret. The doorway, like that within, is quite plain, and has a flat, segmental head under an arch of relief, also segmental, but less flat. It looks as though the lower arch had been inserted to carry the joists of the roof, but it is really original. The pitch of the roof of the forebuilding has been thrice altered, as is shown by the grooves cut in the wall of the turret. The flattest is the latest. The roofs seem to have been of the lean-to character. Whether there was a chamber below the stair, or whether there was a way at the base of the stair into the lower floor of the keep, as has been already pointed out, cannot now be ascertained. It would seem that in the Perpendicular period this forebuilding was much altered, its entrance a little shifted, and in it were placed several piers, 3 feet square, supporting full-centred arches, of 9 feet span, on which the timbers of the floor above were laid. A plain doorway of 6 feet opening was cut in the curtain forming the north end, and in the exterior of the wall an alcove was formed of 13 feet span by 6 feet deep, having a segmental arch, and supported by three plain ribs with a hollow chamfer. This alcove opened upon a terrace, which overlooked the northern part of the outer ward, and formed a sort of landing and staircase, giving a descent of four or five steps from the door to the terrace. The object seems to have been to form a handsome way from the inner ward to the garden north of the keep. The piers and arches might be of the date of Elizabeth or James, but their mouldings and parts of the adjacent walls are clearly earlier, and no doubt the work of the Lancastrian owners, who in that case must have indulged in a garden. Dudley made further alterations, and a part of the south front of the forebuilding still bears the date of 1575, and has Italian ornaments.