Guildford Castle occupied a natural platform of nearly six acres upon the slope of the chalk hill, far below its summit, and from 40 to 80 feet above the river. The platform, inclining gently towards the stream, terminates at about 80 yards from its bank in a low cliff of from 10 to 12 feet high, in parts replaced by, and in parts resting upon, a steep, natural slope or talus, which dies away 40 feet lower down into the meads traversed by the river. The crest of this cliff or talus is occupied by Quarry Street, and forms the west front of the castle. Towards the north, the river is more distant, and the slope of the platform far more gradual. On this side, the High Street and the present town of Guildford intervene between the castle and the river. The keep stands on the eastern and highest part of the platform, and commands the rest of the castle, as the castle commands the town; and here are what appear to be the remains of the English residence. At the foot of the steep, a mound, wholly artificial, but resting upon an inclined natural base, has been thrown up, composed of chalk, in form conical, truncated, and with a level summit, no doubt originally circular, and still nearly so, and about 90 feet diameter. The base is about 200 feet. Between the mound and the adjacent steep hill-side is the main, and perhaps a trace of a second and outer, ditch. This inner ditch, about 60 feet broad and 12 to 20 feet deep, sweeps round the foot of the mound on the east, north, and south sides, the ends dying out on reaching the platform on the west below. The ditch, always dry, has long been cultivated as a garden, and was no doubt once considerably deeper. Its north limb is partially built upon by the houses in Castle Street, and is, in consequence, nearly obliterated. It is traversed at the north-east quarter by a narrow causeway of earth, which, no doubt, represents an older causeway of stone, provided with a drawbridge, and forming a direct entrance for foot passengers and perhaps horses, to the keep. Beyond this, the east and south-east, in the extra-parochial plot called the “Bowling Green,” are very slight traces of what may have been a second and outer ditch, a not unlikely security to have been provided by the inhabitants of the mound against an attack on this the weakest, because the commanded, side.