THE KEEP PLAN INTRODUCTION of a series of curved projections or rounds, so designed that every part of the base could be seen and defended from several parts of the parapet. The whole was further strengthened by a deep ditch cut in the rock. The outer ward had also a lofty wall and deep ditch, and was fortified with round towers. A triangular outwork to the east, also furnished with lofty round towers, guarded the approach from that quarter where the promontory joins the mainland. In 1204 this castle stood a memorable siege by Philip Augustus, by whom it was taken from King John. Fid. 21. Chateau de Provins. Plan. The Castle of Provins (south-east of Paris) is another instance of the various forms which were tried in the twelfth century. It is an octagon on plan (Fig. 21), four of the sides being smaller than the others, and having semicircular projections upon them. These in the upper stories become detached circular turrets, connected in their upper part by a flying buttress with the main keep (Fig. 22). The entrance to the keep was by a drawbridge from the wall of the enceinte. M. Viollet-le-Duc supposes that there were drawbridges from the projecting ledge at the doors on the four sides to the enceinte. A
