This question at least partly revolves around whether you are thinking of "Northern Ireland" in a political sense or a golfing sense. If the former,what has been posted above is the party line and very adequate. If the latter, you will open up such great venues as Portsalon, Ballyliffin, Rosapenna, Narin and Portnoo, Donegal. etc. etc. As I'm sure our Irish friends will confirm, "Ulster" is not just the 6 Counties which happen today to be under British rule.........