▁a ▁single ▁day . ▁Given ▁that ▁it ▁is ▁surrounded ▁on ▁three ▁sides ▁by ▁wat ery ▁regions , ▁it ▁is ▁not ▁imp laus ible ▁that ▁the ▁entire ▁region ▁can ▁be ▁flo oded , ▁as ▁described ▁in ▁the ▁second ▁book , ▁G orm eng h ast . ▁ ▁At ▁the ▁centre ▁of ▁the ▁ear ld om ▁is ▁the ▁vast , ▁largely ▁desert ed ▁castle , ▁whose ▁remaining ▁inhabitants ▁centre ▁their ▁lives ▁on ▁the ▁rit ual ▁surrounding ▁the ▁r uling ▁family ▁of ▁Gro an . ▁The ▁castle ▁is ▁described ▁as ▁being ▁like ▁an ▁immense ▁island ▁of ▁stone , ▁its ▁every ▁outline ▁familiar ▁to ▁the ▁inhabitants , ▁who ▁know : ▁" every ▁bay , ▁in let ▁and ▁head land ▁of ▁the ▁great ▁stone ▁island ▁of ▁the ▁Gro ans , ▁of ▁its ▁she er ▁cl iffs , ▁of ▁its ▁cr umb ling ▁out cro ps , ▁the ▁broken ▁line ▁of ▁the ▁to wers ". ▁Domin ating ▁the ▁iv y - cover ed , ▁cr umb ling ▁castle ▁is ▁the ▁highest ▁tower , ▁the ▁Tower ▁of ▁Fl ints , ▁which ▁is ▁inhab ited ▁by ▁great ▁numbers ▁of ▁ow ls . ▁The ▁castle ▁is ▁so ▁huge ▁that ▁most ▁of ▁the ▁inhabitants ▁do ▁not ▁vent ure ▁outside ▁except ▁for ▁cer emon ies . ▁Out side ▁the ▁castle , ▁cluster ed ▁under ▁the ▁northern ▁walls , ▁is ▁a ▁h odge - pod ge ▁of ▁mud ▁dwell ings ▁inhab ited ▁by ▁the ▁" B right ▁Car vers ", ▁vill agers ▁whose ▁only ▁contact ▁with ▁the ▁arist ocr ats ▁is ▁their ▁annual ▁rit ual