Ideas for rest-stops along the way?

We have a few trips in our rental car that's over 2hrs in length and just wondering if there are quick rest stops we shouldn't miss out on along the way?

I live in Canada, so a 3 or 4 hour trip is not bad at all and we usually do that without stopping but hey, this is a vacation afterall. ;-)

1. Dublin Airport - Kilkenny (~2hrs)
2. Doolin Caves - Connemarra/Galway (~2.5hrs)
3. Galway - Kilcar, Donegal (~4hrs)
4. Donegal - Giants Causeway (~2.5hrs)
5. Giants Causeway - Newgrange then back to Dublin (~2.5hrs)

THANKS!

Just stay off the Motorways (M roads), and stick to the N and R roads. These will take you through every little village and town. If you make regulars stops at pubs and cafes for coffee/tea and snacks you'll see a lot more of Ireland than if you travel the main roads. There are at least a thousand GREAT places to stop on the routes you've planned.

The Donegal-Giants Causeway leg should take two days! As for Giant's Causeway to Dublin you must stop at Carrickarede Rope Bridge and then come and visit us in Cushendall in the beautiful Glens of Antrim wehre Glenariff waterfalls are a must! Good palces to eat in the village of Cushendall as well.

a 3 or 4 hour drive without stopping in Ireland is about 20 times more stressful than the same in Canada, and there's more than 20 times more things to see in a relatively short distance.
Take your time, and meander

Between Dublin and Kilkenny you might stop at Glendalough or Graiguenamanagh