The water by which these two wards were encompassed was on one side a deep and broad lake covering about 16 acres, and on the other side a smaller sheet of water of about 3½ acres. These two waters were connected by cross cuts at each end, traversed, opposite the gatehouses, by drawbridges. One of these dropped upon a _tête du pont_, a sort of hornwork or ravelin of earth, about an acre and a-half in area, and enclosed within a revetment wall duly parapetted, and probably with a stout palisade on the raised ground within. A branch from the lake encircled this work, and a second drawbridge connected it with the ground outside. At the opposite end of the castle another bridge dropped from the middle ward upon the outer ward, a very remarkable work. This was a raised platform nearly 330 yards long by from 14 yards to 36 yards in depth, covering the whole front of the castle, including the two sheets of water. The platform was divided near its centre by a lofty wall embattled on each face, and having a ditch along one of them. On this wall was a strong gatehouse having below a portcullised doorway, with a drawbridge connecting the two parts of the platform, and above, a smaller doorway, also protected by a bridge and portcullis, and guarding the way to the battlements of the outer wall. At one end of the platform was a postern connected with the stables, and at the other a cluster of towers on the outer bank of the lake, containing another postern. In the centre was the great exterior gatehouse, from the gateway of which a bridge dropped upon an enormous pier standing in the middle of the outer ditch, from the exterior face of which a second bridge dropped upon the village street. On the platform was a large corn-mill, and connected with it the dam and sluice by which the waters of the lake were retained and regulated, and which was very strongly fortified. Thus there were two great gates and two posterns at points of the castle distinct from each other, whence large bodies of cavalry could issue, so that the camp of a besieging force could be attacked from four directions, and, in case of failure, the castle could be reached by four entrances, besides two water-gates. In addition to these strategical arrangements, each tower and gatehouse had a portcullised entrance on the ground floor, and in the upper stories the lateral doorways opening on the battlements of the curtains were protected in a similar manner. In a military point of view, Caerphilly is a work of consummate skill. Unfortunately for its historic fame, the settlement of Wales followed so closely upon its erection that it never attained to any great importance.