Yes of course-in all the trains from your home till there-and as you know, a RES must be made for this €* to GB and then its ferry to IE as 2nd isle-and you have to pay for that, with discount on some. And use pass again whilst on the green island with its green trains.

There are 2 main ferry routes-from Holyhead, north of Wales-toward Dublin area (Stena) and from Fishguard, south tip of Wales-to Rosslare-for the south. In the north also toward Belfast from a port that does not have trains -was moved to please the cars some yrs ago