</s> ▁An ▁international ▁flight ▁is ▁a ▁form ▁of ▁commercial ▁flight ▁within ▁civil ▁av iation ▁where ▁the ▁departure ▁and ▁the ▁arrival ▁take ▁place ▁in ▁different ▁countries . ▁ ▁An ▁important ▁difference ▁between ▁international ▁and ▁domestic ▁fl ights ▁is ▁that , ▁before ▁board ing ▁the ▁aircraft , ▁passengers ▁must ▁under go ▁migration ▁formal ities ▁and , ▁when ▁arriv ing ▁to ▁the ▁destination ▁air port , ▁they ▁must ▁under go ▁both ▁imm igration ▁and ▁custom s ▁formal ities , ▁unless ▁both ▁the ▁departure ▁and ▁arrival ▁countries ▁are ▁members ▁of ▁the ▁same ▁free ▁travel ▁area , ▁such ▁as ▁the ▁Sch engen ▁Area . ▁ ▁Air ports ▁serving ▁international ▁fl ights ▁are ▁known ▁as ▁international ▁air ports . ▁ ▁Orig ins ▁One ▁of ▁the ▁first ▁fl ights ▁between ▁two ▁countries ▁was ▁on ▁January ▁ 7 , ▁ 1 7 8 5 , ▁when ▁Jean - Pierre ▁Bl anch ard ▁and ▁John ▁Jeff ries ▁crossed ▁the ▁English ▁Channel ▁in ▁a ▁hot ▁air ▁bal lo on . ▁It ▁took ▁more ▁than ▁a ▁century ▁for ▁the ▁first ▁heav ier - than - air ▁object ▁to ▁repeat ▁this ▁process : ▁Louis ▁Bl éri ot ▁crossed ▁the ▁English ▁Channel ▁on ▁July ▁ 2 5 , ▁ 1 9 0 9 , ▁winning ▁a ▁Daily ▁Mail ▁prize ▁of ▁£ 1 , 0 0 0 . ▁ ▁A viation ▁technology ▁developed ▁during ▁World ▁War ▁I , ▁with ▁av iation ▁between ▁the ▁World ▁Wars ▁seeing ▁the ▁development ▁of ▁international ▁commercial ▁fl ights . ▁There ▁was ▁a ▁combination ▁of ▁aircraft ▁types ▁which ▁included ▁air ships ▁and ▁air