Iarnrod Eireann (IE) operate the national rail service in the Republic of Ireland and Northern Irish Rail (NIR) operate the national rail service in Northern Ireland. IE operate south and west from Dublin Heuston towards Cork and Westport and NIR operate northbound from Dublin Connolly towards Belfast and the north. You can use the IE online timetable and NIR online timetable to plan your trip. PDF downloads are available for all IE Routes including the Dublin Cork IC service and all NIR Routes including the Dublin Belfast Enterprise service.
A comprehensive list of both passenger and freight operators in Ireland can be found on the helpful Railfan Europe website’s Ireland page.
Train times and Tickets
Booking tickets for travel within both the Republic or Ireland and Northern Ireland can be done at stations. Tickets are also available online, information regarding the ticket types, validity and periods available for Irish Rail (IE) and Northern Irish Rail (NIR) can be found on their respective websites.
If choosing to use an Interrail pass, either for just within Ireland, or to pass through Ireland, all the relevant details on the passes, including the different types/lengths of validity available, can be found on the InterRail website.
Finally travel in Europe can be made a lot simpler by using the very, very, helpful smartphone app courtesy of Eurail. This app is available both online and offline and is always up to date (well it has been for the countries I’ve used it in; including for any planned engineering works); for me it was an essential part of my travel in Europe. This app is linked to the Hafas system, which countries like Germany, Austria & Switzerland use for their train planning online tool. Eurail has done what the individual countries haven’t though and made it available offline.
For the Rail Enthusiast
A comprehensive list of Swedish Locomotives by their respective railway system can be found on the Railfaneurope website’s Ireland page. This also explains a bit the various operators of the network and how they have amalgamated over the years.
A detailed map/atlas of the British Railway Systems, which includes Ireland, is available from European Railway Atlas. Alternatively the excellent Baker’s Atlas covers the British Isles & Ireland.