[Illustration: FIG. 31. Shrewsbury. Skipsea, Yorks.] The bailey of Shrewsbury Castle is roughly semilunar and covers nearly an acre. The walls stand on banks, which shows that the first wall was of timber. The Norman entrance arch seems to render it probable that it was in Henry II.'s reign that stone walls were first substituted for a wooden stockade, and the _Pipe Rolls_ contain several entries of sums spent by Henry on this castle.[658] But the first mention of stone in connection with the castle is in the reign of Henry III.[659] In the reign of Edward I., a _jarola_ or wooden wall, which had been raised above the outer ditch in the time of the Barons' War, was replaced by a stone wall.[660] This perhaps refers to the second bailey, now destroyed, which lay to the south of the castle. In the time of Charles I. the castle still had a wooden palisade on the counterscarp of the ditch.[661] The two large drum towers on the walls, and the building between them, now converted into a modern house, belong to a much later period than the walls. The area of the present castle, including the motte, is 4/5 of an acre. The value of the town of Shrewsbury had risen since the Conquest. SKIPSEA, Yorks (Fig. 31).--There is no mention of this castle in Domesday Book, but the chronicle of Meaux Abbey tells us that it was built by Drogo de Bevrère in the reign of William I.[662] This chronicle is not indeed contemporary, but its most recent editor regards it as based on some much earlier document. It was the key of the great manor of Holderness, which the Conqueror had given to Drogo, but which Drogo forfeited by murdering his wife, probably on this very site. The situation of Skipsea is remarkable, but the original plan of Kenilworth Castle presented a close parallel to it. The motte, which is 46 feet high, and 1/5 of an acre in space on top, is separated from the bailey by a level space, which was formerly the Mere of Skipsea, mentioned in documents of the 13th century, which reckon the take of eels in this mere as a source of revenue.[663] The motte thus formed an island in the mere, but as an additional defence--perhaps when the mere began to get shallow--it was surrounded by a bank and ditch of its own. No masonry is to be seen on the motte now, except a portion of a wing wall going down it. It is connected with its bailey on the other side of the mere by a causeway which still exists. This bailey is of very unusual size, covering 8-1/4 acres; its banks still retain the name of the Baile Welts, and one of the entrances is called the Baile Gate. Skipsea Brough, which no doubt represents the former _burgus_ of Skipsea, is outside this enclosure, and has no defences of its own remaining. A mandate of Henry III. in 1221, ordered the complete destruction of this castle,[664] and it was no doubt after this that the earls of Albemarle, who had succeeded to Drogo's estates, removed their _caput baroniæ_ to Burstwick.[665]