▁large ▁share ▁of ▁these ▁structures , ▁including ▁the ▁Car n ac ▁stones ▁and ▁the ▁Bro ken ▁Men h ir ▁of ▁Er ▁Gra h ▁in ▁the ▁Loc mar ia quer ▁meg al ith s , ▁the ▁largest ▁single ▁stone ▁ere cted ▁by ▁Ne ol ith ic ▁people . ▁ ▁Gall ic ▁era ▁ ▁During ▁the ▁proto histor ical ▁period , ▁Brit t any ▁was ▁inhab ited ▁by ▁five ▁C elt ic ▁tribes : ▁ ▁The ▁Cur ios ol ita e , ▁who ▁lived ▁around ▁the ▁present ▁town ▁of ▁Cor se ul . ▁Their ▁territory ▁en comp ass ed ▁parts ▁of ▁C ô tes - d ' Ar mor , ▁Il le - et - V ila ine ▁and ▁Mor b ih an ▁départ ements . ▁ ▁The ▁Nam net es , ▁who ▁lived ▁in ▁the ▁current ▁Lo ire - At lant ique ▁département ▁( in ▁today ' s ▁administrative ▁région ▁of ▁Pays ▁de ▁la ▁Lo ire ), ▁north ▁of ▁the ▁Lo ire . ▁They ▁gave ▁their ▁name ▁to ▁the ▁city ▁of ▁N antes . ▁The ▁south ▁bank ▁of ▁the ▁river ▁was ▁occupied ▁by ▁an ▁al lied ▁tribe , ▁the ▁Amb il at res , ▁whose ▁existence ▁and ▁territory ▁remain ▁uns ure . ▁ ▁The ▁Os ism ii , ▁who ▁lived ▁in ▁the ▁western ▁part ▁of ▁Brit t any . ▁Their ▁territory ▁compr ised ▁the ▁Fin ist ère ▁département ▁and ▁the ▁western ▁extrem ity ▁of ▁C ô tes - d ' Ar mor ▁and ▁Mor b ih an . ▁ ▁The ▁Red ones ▁( or