In the centre rises the great donjon tower, which stands as an enduring memorial of William de la Grace, the great Earl Mareschal, who in all probability designed the main fabric of the castle as we see it to-day. An imposing _coup d'oeil_ of the ruins may be obtained by turning down Dark Lane, crossing the old bridge that spans the stream hard beneath the castle, and entering a timber-yard close by. Prominent in the view is a lofty tower, mantled in glossy-green ivy and pierced with graceful pointed windows, that soars from the river brink, enclosing, deep below its foundations, that 'mervelous vault called the Hogan,' whence the garrison in olden times drew their supplies of water. Beside the tower extends a long stretch of ivy-clad wall, rooted in the living rock and broken at intervals by shapely turrets; over which peep the upper works of the central keep. The spars and cordage of some stranded coasting vessels, and a group of men calking their weather-beaten timbers, lend an added charm to an exceedingly picturesque scene. We are indebted to Leland for the ensuing description of the castle as it appeared in the days of bluff King Hal: 'The Castel stondeth hard by the waul on a hard Rokke, and is veri large and stronge, being doble wardid. In the atter ward I saw the chaumbre wher King Henri the vii was borne; in knowledge whereof a chymmeney is now made, with the armes and Badges of King Henri vii. In the botom of the great stronge Towr, in the inner warde, is a mervelous vault called the Hogan.' Another chronicler of very different stamp, the late Professor Freeman, thus records his impressions of this interesting pile: 'Pembroke Castle remarkably combines elevation and massiveness, so that its effect is one of vast general bulk. It is another conspicuous instance of the majesty often accruing to dismantled buildings, which they could never have possessed when in a perfect state.' Traversing the outer barbican that protected the deep-set entrance, we pause to marvel at the elaborate defences of double portcullis and thick, nail-studded doors, commanded by loopholed guard-chambers, set within the gloomy arches of the gate-tower. The latter presents a stately front, flanked by attached round towers, overlooking the inner court; and contains a number of fine apartments for the accommodation of distinguished guests.