▁municipal ▁unit ▁has ▁an ▁area ▁of ▁ 5 9 . 3 2 5 ▁km 2 . ▁Gast ou ni ▁is ▁situated ▁in ▁a ▁flat ▁rural ▁area , ▁ 5   km ▁from ▁the ▁I onian ▁Sea . ▁The ▁river ▁P ine ios ▁flows ▁into ▁the ▁sea ▁near ▁Gast ou ni . ▁The ▁town ▁is ▁ ▁south ▁of ▁And rav ida , ▁ ▁east ▁of ▁Var th ol om io , ▁ ▁north west ▁of ▁Am ali ada ▁and ▁ ▁north west ▁of ▁P yr g os . ▁The ▁population ▁of ▁the ▁town ▁proper ▁was ▁ 7 , 4 8 5 ▁in ▁ 2 0 1 1 . ▁The ▁Greek ▁National ▁Road ▁ 9 / E 5 5 ▁( Pat ras ▁- ▁P yr g os ) ▁and ▁the ▁railway ▁from ▁Pat ras ▁to ▁P yr g os ▁pass ▁east ▁of ▁Gast ou ni . ▁There ▁is ▁a ▁ 1 2 th - century ▁By z antine ▁church ▁in ▁the ▁south western ▁quarter ▁K athol iki . ▁ ▁Sub div isions ▁The ▁municipal ▁unit ▁Gast ou ni ▁is ▁sub div ided ▁into ▁the ▁following ▁communities : ▁Gast ou ni ▁K ard ia ka ft i ▁K avas ila ▁K oro ivos ▁Le f k och ori ▁Pala io ch ori ▁R oup aki ▁ ▁Population ▁history ▁ ▁People ▁ ▁Nik os ▁K acht itis , ▁writer ▁The ▁S is in is ▁family ▁Ch rys anth os ▁S is in is ▁Georg ios ▁S is in is , ▁one ▁of ▁the ▁famous ▁Greek ▁revolution ary