W arring ah ▁Express way ), ▁which ▁was ▁originally ▁planned ▁to ▁link ▁the ▁Sydney ▁Har bour ▁Bridge ▁with ▁the ▁Northern ▁Be aches , ▁but ▁today ▁termin ates ▁just ▁south ▁of ▁Castle c rag ▁in ▁N are mb urn . ▁ ▁The ▁Griff ins ' ▁vision ▁ ▁In ▁ 1 9 2 1 , ▁Walter ▁Bur ley ▁Griff in ▁( arch itect ▁and ▁landscape ▁architect ) ▁and ▁Mar ion ▁Mah ony ▁Griff in ▁( arch itect ▁and ▁artist ) ▁began ▁design ing ▁Castle c rag ▁a ▁model ▁resident ial ▁sub urb ▁that ▁was ▁sympath etic ▁to ▁the ▁Australian ▁natural ▁environment . ▁ ▁Upon ▁arriv ing ▁in ▁Australia ▁in ▁ 1 9 1 3 , ▁Walter ▁Bur ley ▁Griff in ▁was ▁struck ▁by ▁the ▁natural ▁beauty ▁of ▁the ▁Sydney ▁Har bour , ▁and ▁at ▁the ▁first ▁Australian ▁town ▁planning ▁conference ; ▁he ▁emphas ised ▁that ▁best ▁planning ▁practice ▁should ▁respect ▁the ▁natural ▁character ▁of ▁the ▁site ' s ▁landscape . ▁Griff in ▁formed ▁ ▁the ▁Gre ater ▁Sydney ▁Development ▁Association ▁( G SD A ) ▁together ▁with ▁several ▁invest ors ▁( Gr iff in ▁holding ▁more ▁than ▁ 5 0 % ▁of ▁the ▁voting ▁rights ). ▁This ▁company ▁purchased ▁and ▁developed ▁Castle c rag ▁with ▁Griff in ▁as ▁man aging ▁director / le ad ▁pl anner . ▁Griff in ' s ▁design ▁for ▁Castle c rag ▁was ▁based ▁on ▁careful ▁planning , ▁respect ful ▁of ▁the ▁particular ▁site , ▁and ▁he ▁was ▁dis may ed ▁by ▁the ▁layout ▁of ▁Sydney ' s ▁sub ur bs