 In the Republic of Ireland , counties form the basis of the system of local government . Counties Dublin , Cork , Limerick , Galway , Waterford and <unk> have been broken up into smaller administrative areas . However , they are still treated as counties for cultural and some official purposes , for example postal addresses and by the Ordnance Survey Ireland . Counties in Northern Ireland are no longer used for local governmental purposes , but , as in the Republic , their traditional boundaries are still used for informal purposes such as sports leagues and in cultural or tourism contexts . 
