The Irish rail network is operated by Irish Rail/Iarnrod Eireann. The Network operates, primarily, as a hub and spoke system, centred on Dublin City Centre. Iarnrod Eireann provide an excellent on-line interactive timetable and route planner which you can access here.
A regular bus service operates from Waterford Train station to Tramore bus station, further details are available from the Bus section on the menu.
Other Useful Links