We are looking for a place to stay for two days on our way from Letterkenny to Doolin.
We will take a day trip around the area on our second day. Thinking of Westport or Sligo, any suggestions?
Thanks,
Terry

You might want to further modify this post so it clearly shows Ireland.

Either is good, but I suspect that more people here will recommend Westport. There is a lot of good stuff to see around Sligo.

Either place would be good. Sligo has some interesting places around it associated with the poet William Butler Yeats. You can drive out around Lough Gill, Lake Isle of Inishfree - driving around the lake via Dromahair and back to Sligo town. On your way from Letterkenny as you approach Sligo you pass Benbulben and Drumcliffe where you can visit the grave of Yeats - "Cast a cold eye on life on death, horseman pass by." Just outside the town you can visit Rosses Point beach or Strandhill and seaweed baths. The town itself has some nice shops and pubs. Hardogans is a lovely pub to drop into during the day. Visit the wood carver Michael Quirke in his shop on Wine Street. (As you might guess I know Sligo area pretty well, I am originally from there). Check out free walking tours of the town from the tourist office.
Westport is more popular with tourists. Again lots of things to do around it - Drive out to Croagh Patrick - if you are feeling energetic climb Croagh Patrick and get a great view of all the islands in Clew Bay. Westport has some great pubs and shops - inclined to be a little more touristy than Sligo in Summertime.
You could get a bit of both by deciding to do two nights in one and get around the area but then maybe just stopping for lunch in the other and having a quick view of it.