Ireland in early March

Here's the route map for Irish Rail Station and Route Map. As you can see, there is rail service to much (but not all) of the country. Like most public transit systems, it was designed for locals, not necessarily for routes that tourists might want. For example, inconveniently for us visitors, it's not very useful for those who want to follow along the lovely west coast.

Most tourist attractions don't really "close" in the off season (in part because most tourist attractions are either outdoor natural places, or are just Ireland itself).

In early March, you should expect fairly short days but mostly expect some atmospheric moisture - you may luck out and get sunny days, but there's a reason everything is so green that they call it "the emerald island" - lots of rain. You want need to be prepared for that with appropriate clothing and footwear.

Dingle is a long way from Dublin, and it'll take longer to get between there and Dublin than most people expect. You can get there, but on a trip as short as yours, you will need to be careful and time things. Tralee could work, but check the train schedules.

We're going in early March as well and I wonder about the weather. (We've been many times in summer.)
Maybe spend two nights in Dublin then head to Galway, spend the weekend in Galway? There would certainly be an easy connection for your daughter back from there, and there's plenty to do in the city no matter what the weather. If the weather is good, you could potentially do a day trip to Inishmore on Sunday, taking the ferry from Rossaveal.

Thanks to you both! Our daughter will be visiting Galway/Aran at some point as part of her study abroad program, so we would like to save that destination for a bit later in our trip, after she has departed us and returned to Dublin. Galway would have been my preference to begin the trip, but I think we will need to either do day trips with Dublin as a base for the first few days, or rent a car as soon as we land and head south (or board a train/bus and head south). I'm just having difficulty with the timeline -- figuring out where we should be 4 days into an 8-day itinerary to make it easier for her to get back.

rent a car as soon as we land and head south (or board a train/bus and
head south)

Many experienced travelers here (including me) would suggest that flying halfway around the world, arriving exhausted and jetlagged, then immediately jumping in a car in a foreign country where driving is "wrongside" for you, and heading off on the road is not a safe or wise choice. Some people do it and advocate it. I know when I've landed in Ireland and stepped off a trans-Atlantic flight, I was in no condition to be behind the wheel.

There are comfortable, easy, cheap, stress-free -- and completely safe -- bus ("coach") options right at the airport, and trains (requires a connection in Dublin itself) that are great alternatives to risking that post-flight drive. Step off the bus or train at your destination, get a good night's sleep, then wake up the next morning feeling good, rent that car, and off you go. Something to consider.

Maybe land, meet up with your daughter at the airport or train station, hop the train and head for somewhere in the southwest. You'll be within striking distance of Dingle. A few days later, when your daughter needs to head back to Dublin, find a train station that works, drop her there, and you continue exploring the southwest, until you're ready to head back to Dublin, too...then drop the car, hop on the train/bus, and let someone else do the driving.

One other thing, be sure to look at bus service. In my experience the bus network in Ireland is more extensive and just as fast as the trains. The buses themselves are nicer and more comfortable than in the US.

Great points -- thank you!

We have visited Ireland twice in mid-March. The first time, when we stayed at a B & B in Dun Laoghaire it was chilly--especially as we were near the water. There were two days when there was a very cold and steady rain and intense wind. We were happy for our lined raincoats and layers underneath! The second time we stayed in a small Airbnb apartment and though we were happy to have those raincoats and extra layers with us, the weather was milder and we were more comfortable. We did take the train down to Kilkenny and stayed in an Inn--loved it! My husband went up the tower at St. Canice's and loved it but he said it was narrow and if anyone had claustrophobia or was "tradionally built" as Alexander McCall Smith's Mma Ramotswe would say, they would have been uncomfortable. I toured the inside of the church instead.

We didn't find that much was closed. Did take a bus tour to Bru Na Boinne and the Hill of Tara with Mary. . . --she's recommended in RS's Ireland book. Loved that, too.

Thank you for the intel!