The keep is of rough rubble masonry, with ashlar quoins and dressings. It has neither plinth, set-off, nor string, and preserves its exterior dimensions to the summit. Each angle is capped by two pilasters of 9 feet breadth by 11 inches projection. They unite at the angles, which are solid. The two southern angles are supported by extravagantly-large low buttresses, of modern addition, but it is said they were preceded by buttresses somewhat similar, though of much slighter character.
The keep is 33 feet square and about 43 feet high. The walls are 8 feet thick at the base, and consequently enclose a chamber 17 feet square. This is the basement floor, and at the ground level. It is 9 feet high, and the floor, which covered it above, and is now gone, rested upon nine beams, and was therefore immensely strong. The north, south, and west walls are each pierced by a loop, set in a round-headed recess, 5 feet broad and 5 feet high to the springing. Two of these loops have been converted into open breaches, and the third, to the north, has been walled up and the recess covered with a flat lintel. This floor must have been entered from the room above by a trap and ladder. It was, as usual, a store, the value of these strong small towers depending upon their being well provisioned.
The first floor rested upon a set-off of a foot, and is therefore 19 feet square, with walls 7 feet thick. It is 23 feet high. It has in the north and south walls small square-headed loops, placed in round-headed recesses of 4 feet 6 inches opening. In its west side, close to the north end, is a doorway 2 feet 10 inches broad and 8 feet high, round-headed. In the north wall, on each side the loop, is a door. One of these, flat-topped, of 2 feet 6 inches opening and 6 feet high, leads through a small mural lobby, 4 feet 8 inches by 3 feet 2 inches, into a well-stair, 7 feet diameter, which occupies the north-east angle, and commencing at this level, ascends to the battlements by fifty-four steps. The other door, of 2 feet 11 inches opening, 8 feet high, and round-headed, leads by a passage bent at a right angle and having a barrel vault, into a plain mural chamber, 7 feet by 5 feet, also barrel-vaulted, and which, no doubt, had a loop in its west wall. This wall, however, is now broken away, so that the chamber has much the aspect of an entrance-lobby, which it certainly was not.
The second, or uppermost, floor rests upon a set-off of 2 feet, and is therefore 23 feet square, with walls 5 feet thick, and at present 11 feet high. Singularly enough, it shows no trace of any wall-opening whatever, as though it had been added in modern times for effect only, which, however, does not appear to be the case. The staircase, however, has certainly been repaired, and no doubt originally opened into this floor. The wall at the interior angle is thickened somewhat to give space for the stair. The walls may have been a foot or so higher, but scarcely more. The parapet is gone, and was probably another 5 feet. The north-east angle seems to have ended in a small square turret.
The principal entrance was evidently on the first floor, in the east wall, reached by an external stair built against the wall, and ascending from the south end. This is clear from the position and dimensions of the doorway, and from the absence of a loop on this side of the basement, where it would have been covered by the staircase.
The small door of the west wall of the same floor seems to have led upon the rampart of the adjacent curtain, here only 11 feet from the keep. There is such a door at Arques and at Rochester, and also at Helmsley and Adare. This keep contains no fireplace nor garderobe, nor ornament of any kind.
The lower ward has been so altered for domestic purposes, and is so built over, as to be very obscure. It was at least eight or ten times the area of the upper ward, and descended 280 feet down the slope, with an extreme breadth of 150 feet. The modern dwelling-house is built upon the south-east curtain, and no doubt represents, and probably contains, part of the old domestic buildings. Buck gives a view of the southern front of this ward, and shows a large round tower upon one of the angles not now seen.
A convenient ascent skirts the foot of the west curtain, or rather of the cliff upon which it stands, and enters at the upper end of the lower ward, just below the keep. This, however, is probably modern. The old way seems to be represented by the road from the town, which rises on the other or eastern side.
About a furlong to the south of, and much below the castle is a steep straight bank of earth with an exterior ditch, probably an outwork covering the foot of the hill.
The castle is the property of the Duke of Buccleuch, whose steward for the Honour of Clitheroe resides here, and allows visitors to enter the keep unchallenged. The chief rents and royalties of the Honour are vested in the Duke, and are said to be valuable. All is neatly kept, and is in as substantial repair as becomes a ruin; but his Grace’s most commendable zeal does certainly a little obscure the fabric it preserves, and it is to be regretted that the new work was not made more clearly distinguishable from the old.