Although the castle stands upon a promontory of rock, there is a broken shelving space between its wall and an actual cliff in which the rock terminates below, and it is this space, which lies to the west and north, which has been enclosed as the outer ward, the containing wall of which crowns the cliff and where necessary is supported by a revetment. This outer wall begins below the north-east bastion of the middle ward, whence a door with steps seems to have led down about 10 feet to its ramparts. It is at that point a very stout wall, about 14 feet high, with a parapet on the western face, thus defending the ditch and main bridge from an enemy who might be in possession of the outer ward and be disposed to turn the eastern flank. It is probable, however, that the wall had a double parapet, for lower down, where the wall faces the north, the parapet is on that face. Near the bastion there seems to have been a door in this wall, giving a passage from the outer ward to the ditch. Lower down, where the wall stands on the cliff, it is thinner, and in parts much broken away. Still lower it is more perfect and much stronger, and where it turns the north-west corner of the rock, opposite the railway station, it is of great thickness, and has a rampart wall and parapet towards the sea, above the level of which it is about 30 feet; near this point is the lower water-gate, a regular postern, in a small rectangular shoulder in the wall. A roadway of about 5 yards or 6 yards long, cut in the rock, rises from the marsh 10 feet or 12 feet, and upon it, in front of the portal, was a drawbridge with a pit 12 feet deep, and within the portal a short shoulder-headed passage closed apparently by a door, but without any portcullis. Beyond this a flight of open stairs niched in the curtain ascended to an embattled platform over the gate. From the lower gate, the road leads up a rather steep passage formed partly by taking advantage of a shelf and partly by quarrying the rock, the outer side being protected by a wall 8 to 10 feet high and from 2 to 3 feet thick, and looped at about every 20 feet. As the inner side of the roadway is the irregular face of the cliff, it varies much in breadth, from 6 to 12 feet or more. This road, continually ascending, thus covers the whole seaward face of the castle rock, and at about 70 feet or 80 feet in height it terminates in the middle gate, which is about 20 feet below the base of the south-western bastion of the middle ward. Here, a shoulder in the rock is occupied by a second gatehouse, fortified as the first, with a drawbridge and a deep pit, which below has two arches, one for the discharge of water from the pit and the other, which may be merely to support the side wall of the gatehouse, but which may also be a sewer from the castle. Outside this gate is a platform which rakes the face of the wall of the passage below, while above and within the gate is a broad bastion, whence commences the second traverse.