Dingle to Dublin - stopping to see Rock & Kilkenny worth it forgoing a day in Dublin

We have visited most of the places on your list. Everyone likes different things, so I can only share our reactions:

Dublin - just another big city. Visited once, have never revisited. I think it would be more interesting if one had a lot of Irish ancestry. We prefer to spend our time enjoying the scenery which is mostly on the west coast.

Glendalough was very interesting and atmospheric. I would choose it over Kilkenny (interesting medieval bits) or the Rock of Cashel . To be fair, the Rock was heavily shrouded in tarps and scaffolding when we visited. A visit there takes about two hours.

We spent half a day at the Causeway which seemed like plenty of time. It's far away from your other destinations. It is interesting because it is a geological oddity.

Dingle is charming, so is the Ring of Kerry and the Beara Peninsula. That area, Connemara, and Inishmore (reached by boat from Roundstone ? near Galway) have been the highlights of our trips.

Honestly I liked Kilkenny and Glendalough(both on day trip on bus from Dublin) better than Dublin. I was underwhelmed by the Book of Kells. However I loved the archeological museum in Dublin.

You can’t go wrong here. All of the options you present have the opportunity to be special. It depends on what you want to prioritize. You can’t see everything on this trip. Assume that you’ll be back again someday.
We have made four trips to Ireland. We prefer the West Coast. Our most special memories are of Connemara, Kylemore, the Cliffs, the Burren, Slea Head and Trad in Dingle.
That said, the Rock, Kells, Kilmainham are important sites that I’m glad I’ve seen. Kells was important to me, but I can see why it might disappoint some. The Long Library was pretty awesome though. We didn’t have the most skilled guide at the Rock. Perhaps others have had different experiences.

Just another take on things.

Dublin....a quick visit was enough for us both times we went there. We VASTLY prefered the Southwest, Donegal and Wicklow. Book of Kells underwhelming in the extreme....especially if you get stuck in a long line to see it. Don't drive there.....it's a nightmare. Otherwise it's not hard to get around on public transportation. It's a city. If you love cities spend an extra day....it's a nice city.....nothing amazing compared to many other but some good interesting stuff.....but in the end......it's a city......been there done that.

Cashel....an excellent stop. Really nice because it's easily done in 1-2 hours (just try to avoid peak tourist times). Only an hour away from Cashel is Glendalough ....one of the absolute gems of Ireland .... totally worth time away from Dublin.

Kilkenny and surrounding area....very nice,lots to offer.....but better options......Cashel and Glendalough with a spin through the Wicklow Mountains !!!!

Newgrange (Bru Na Boinne) is awesome just outside Dublin....better than any stop in Dublin for us.

Giants Causeway.....a long way away. Interesting...though there are similar formations around the world. When we went it was BEYOND overrun by tourists which was frustrating....for us not worth the time. Love the town of Malin and Malin Head far more wild, not overrun and beautiful.

Strongly urge other options besides that extra Dublin day. A day in Cashel/Glendalough v. A day in Dublin.....it's not even close for us....Cashel/Glendalough by a mile.

I love Dublin. There is so much to do and see. I would highly recommend a walking tour of the City. One day is no where near enough in my opinion. I would forego Kilkenny and the Rock of Cashel for another day in Dublin

I am sure that you are already know this but make sure to pre-purchase your gaol tickets as they sell out. I would do the same for the book of Kells

You have two good choices. It’s more a matter of what you prefer.

You can see the Book of Kells, Trinity and Gaol in one day; however, it would be a busy day. If you’re o.k. with that, then fine. I enjoyed doing two exhibits a day with time to walk through neighborhoods, etc. I toured the Gaol and the GPO History Exhibit in one day; the two give you a different perspective of Ireland’s history. I toured the Kells and Trinity on another day. However, I had more time in Ireland than you have.

If I had to choose between Glendalough and Cashel, I would take Glendalough because it offers more variety of structures and pleasant walks along the way. Trying to see Cashel, Kilkenny and Glendalough in one day would be a bit rushed. Kilkenny is a scenic town with nice walks and several interesting historical sites, so it’s a worth a stop if you’re o.k. with only having one day in Dublin.