eb u ild ing ▁into ▁the ▁keep ▁was ▁protected ▁by ▁a ▁port c ull is . ▁ ▁The ▁stone - built ▁keeps ▁of ▁the ▁ 1 1 th   century ▁generally ▁had ▁simple ▁plans , ▁with ▁few ▁rooms ▁and ▁an ▁un comp licated ▁layout . ▁Ro chester ' s ▁keep ▁be ars ▁test ament ▁to ▁a ▁developing ▁complexity , ▁and ▁provides ▁an ▁early ▁example ▁of ▁a ▁keep ▁divided ▁into ▁separate ▁areas ▁for ▁the ▁lord ▁and ▁his ▁ret inue . ▁The ▁thick ness ▁of ▁the ▁walls ▁allowed ▁rooms ▁to ▁be ▁built ▁into ▁them , ▁as ▁can ▁also ▁be ▁seen ▁at ▁the ▁Hed ingham ▁Castle ' s ▁contempor aneous ▁keep , ▁or ▁the ▁slightly ▁later ▁one ▁at ▁D over . ▁The ▁keep ' s ▁interior ▁is ▁divided ▁for ▁its ▁entire ▁height ▁by ▁a ▁cross ▁wall ▁running ▁east – west . ▁The ▁ground ▁floor ▁was ▁used ▁for ▁storage , ▁with ▁the ▁three ▁store ys ▁above ▁providing ▁accommod ation . ▁The ▁first ▁floor ▁probably ▁contained ▁a ▁hall ▁and ▁great ▁chamber , ▁divided ▁by ▁the ▁cross ▁wall . ▁This ▁level ▁may ▁have ▁been ▁the ▁accommod ation ▁of ▁the ▁castle ' s ▁const able ▁who ▁looked ▁after ▁it ▁during ▁the ▁owner ' s ▁absence . ▁There ▁is ▁a ▁room ▁called ▁" G und ulf ' s ▁Chamber " ▁built ▁into ▁the ▁thick ness ▁of ▁the ▁wall ▁in ▁the ▁north - west ▁corner ; ▁it ▁may ▁well ▁have ▁been ▁the ▁const able ' s ▁private ▁chamber . ▁The ▁second ▁floor ▁contained ▁the ▁keep ' s ▁best ▁accommod ation ▁and ▁some