Parking to take a train into Dublin

I would start with these websites:

Irish Rail: http://www.irishrail.ie/

Bus Eireann: http://www.buseireann.ie/

I did a bit of research and it looks like you'd have to park at the station in Drogheda and then take the train to Connolly Station. If you don't mind a little walk, Trinity College is not far by foot. I think you can take either a bus or street car from Connolly to Pearse Street Station, which is at the back of Trinity College. I would walk from Connolly, though, because there are interesting things to look at on the way such as the Famine Memorial statues, the Custom House, the River Liffey, which you must cross in order to get to the college area.

You can also take the bus. And I found that some searches on the Irish Rail site gave only bus options, but then I also found a train that starts in Belfast and ends in Dublin, with Drogheda being the last stop before Dublin so you don't have to stop in all of the places in between.

Thanks so much. I'll check it out.

Why go all the way around Dublin and well north to Drogheda only to backtrack to Dublin?

I assume you'll be taking the N 7 from Limerick to Dublin. As you approach Dublin the N 7 follows Naas Road. Just after you cross the M 50 you will come to Long Mile Road. City buses 51b and 51c go directly from Long Mile Road to Aston Quay which is on the south bank of the Liffey River and just north of Trinity College.

Take the bus back to Long Mile Road and drive north on the M 50, staying on it as it swings east, and taking it to where it meets the M 1 just south of the Dublin airport. Take the M 1 north and then take the route of your choice to Bettystown.

See the Dublin Bus timetables.

Very true, Tim. I didn't read the question correctly. I was thinking that once they are in Bettystown they'd like to visit Dublin, but now I see they want to stop on the way. (Sorry, Lyn, I hope you listen to Tim and not me. :) )