Gundulph, Bishop of Rochester (1077), whose name still survives here and there in connection with charities and in other ways in the "ancient city," appears to be entitled to the credit of having commenced to build the present massive square Tower or Keep, the surviving portion of a magnificent whole, sometimes called "Gundulph's Tower," "towards which he was to expend the sum of sixty pounds," and this structure ranks as one of the most perfect examples of Norman architecture in existence. Other authorities ascribe the erection to Odo, Bishop of Bayeux and Earl of Kent, half-brother to William the Conqueror, who is described by Hasted as "a turbulent and ambitious prelate, who aimed at nothing less than the popedom." Later, in the reign of William Rufus, it was accounted "the strongest and most important castle of England." It was so important that Lambarde, in _A Perambulation of Kent_, says:--"It was much in the eie of such as were authors of troubles following within the realme, so that from time to time it had a part almost in every Tragedie." Mr. Robert Collins, in his compact and useful _Visitors' Handbook of Rochester and Neighbourhood_, quoting from another ancient historian, says that "In 1264, King Henry III. [who in 1251 held a grand tournament in the Castle] 'commanded that the Shyriffe of Kent do set aboute to finish and complete the great Tower which Gundulph had left imperfect.'" About 1463, Edward IV. repaired part of the Castle, after which it was allowed to fall into decay. The instructions to the "shyriffe" were no doubt necessary; for although L60 would probably go a great way in the time of Bishop Gundulph, the modern aesthetic builder would do very little indeed for that sum, towards the erection of such an impregnable fortress as Rochester Castle, the walls of which vary from eight to thirteen feet in thickness, whatever his progenitor may have done in 1077. The Keep--the last resort of the garrison when all the outworks were taken--is considered so beautiful that it is selected, under the article "Castle" in the last edition of the _Encyclopaedia Britannica_, as an illustration of Norman architecture, showing "an embattled parapet often admitting of chambers and staircases being constructed," and showing also "embattled turrets carried one story higher than the parapet." There is also a fine woodcut of the Castle at p. 198 of vol. v. of that work.