I've been in Dundalk and often drove through it when visiting Dublin. It's a charming enough town (nothing like Belfast of course

Since emigrating to Ireland I've explored Dublin, Belfast, Dundalk, Longford, Lisburn, Dungannon, (London)Derry, Newcastle, Bray, Dun Laoghoire, Dalkey, Limerick, Galway, Aran Islands, Wicklow, Glendalough national park, and Newbridge (but that latter was really nothing). Especially Belfast, Derry and Galway are really nice (despite an unsuccesful romance in Galway, the memories are sweet and I still like to visit the town again). The only thing bad about Ireland is that rain, but being originally from Belgium I'm kinda used to that!