semicircular towers along its course and three great gateways besides posterns.  Edward I built this wall in order to subjugate the Welsh, and also the walls round Carnarvon, some of which survive, and Beaumaris.  The name of his master-mason has been preserved, one Henry le Elreton.  The muniments of the Corporation of Alnwick prove that often great difficulties arose in the matter of wall-building.  Its closeness to the Scottish border rendered a wall necessary.  The town was frequently attacked and burnt.  The inhabitants obtained a licence to build a wall in 1433, but they did not at once proceed with the work.  In 1448 the Scots came and pillaged the town, and the poor burgesses were so robbed and despoiled that they could not afford to proceed with the wall and petitioned the King for aid.  Then Letters Patent were issued for a collection to be made for the object, and at last, forty years after the licence was granted, Alnwick got its wall, and a very good wall it was—­a mile in circumference, twenty feet in height and six in thickness; “it had four gateways—­Bondgate, Clayport, Pottergate, and Narrowgate.  Only the first-named of these is standing.  It is three stories in height.  Over the central archway is a panel on which was carved the Brabant lion, now almost obliterated.  On either side is a semi-octagonal tower.  The masonry is composed of huge blocks to which time and weather have given dusky tints.  On the front facing the expected foes the openings are but little more than arrow-slits; on that within, facing the town, are well-proportioned mullioned and transomed windows.  The great ribbed archway is grooved for a portcullis, now removed, and a low doorway on either side gives entrance to the chambers in the towers.  Pottergate was rebuilt in the eighteenth century and crowns a steep street; only four corner-stones marked T indicate the site of Clayport.  No trace of Narrowgate remains."[4]

As the destruction of many of our castles is due to the action of Cromwell and the Parliament, who caused them to be “slighted” partly out of revenge upon the loyal owners who had defended them, so several of our town-walls were thrown down by order of Charles II at the Restoration on account of the active assistance which the townspeople had given to the rebels.  The heads of rebels were often placed on gateways.  London Bridge, Lincoln, Newcastle, York, Berwick, Canterbury, Temple Bar, and other gates have often been adorned with these gruesome relics of barbarous punishments.

How were these strong walls ever taken in the days before gunpowder was extensively used or cannon discharged their devastating shells?  Imagine you are present at a siege.  You would see the attacking force advancing a huge wooden tower, covered with hides and placed on wheels, towards the walls.  Inside this tower were ladders, and when the “sow” had been pushed towards the wall the soldiers rushed up these ladders and were able to fight on a level