s ▁Bridge . ▁ ▁Central ▁City ▁and ▁Ke yst one ▁City , ▁from ▁the ▁current ▁Flash ▁com ics , ▁are ▁shown ▁as ▁tw in ▁cities . ▁Before ▁the ▁ 1 9 8 5 - 8 6 ▁min is eries ▁Cris is ▁on ▁In finite ▁Earth s , ▁Central ▁and ▁Ke yst one ▁are ▁presented ▁as ▁located ▁in ▁the ▁same ▁space ▁but ▁on ▁different ▁parallel ▁Earth s . ▁ ▁An kh - M orp ork , ▁from ▁Terry ▁Pr atch ett ' s ▁Disc world ▁nov els , ▁is ▁referred ▁to ▁as ▁" the ▁tw in ▁cities ▁of ▁proud ▁An kh ▁and ▁p est il ent ▁Mor p ork " ▁ ▁D uck burg ▁and ▁St . ▁Can ard ▁were ▁dep icted ▁in ▁the ▁cart oon ▁Dark wing ▁D uck ▁as ▁sister ▁cities ▁connected ▁by ▁a ▁bridge , ▁very ▁similar ▁to ▁Oak land ▁and ▁San ▁Francisco . ▁ ▁Hel ium , ▁from ▁the ▁Bar so om ▁series ▁of ▁nov els ▁by ▁Ed gar ▁R ice ▁B urr ough s , ▁consists ▁of ▁the ▁tw in ▁cities ▁Gre ater ▁Hel ium ▁and ▁L esser ▁Hel ium . ▁ ▁Bes ź el ▁and ▁Ul ▁Q oma ▁in ▁ ▁China ▁Mi é ville ' s ▁novel ▁The ▁City ▁& ▁the ▁City ▁are ▁inter tw ined ▁tw in ▁city - states ▁in ▁Eastern ▁Europe ▁whose ▁inhabitants ▁have ▁trained ▁themselves ▁to ▁only ▁see ▁the ▁city ▁they ▁live ▁in ▁and ▁un see ▁the ▁city ▁they ▁don ' t . ▁ ▁See ▁also ▁▁ ▁List ▁of ▁divided ▁cities ▁ ▁Cross -