I went to meet a friend in Dublin 2 weeks ago…
Get ready for lots of people drinking and seeing hen/stag dos everywhere - it’s a major part of the city.
Trinity College and Book of Kells is worth seeing, especially the Library. Amazing 2 story bookshelves.
The needle sculpture is great and you won’t miss it.
Foodwise, try the Ulster Fry-up if your heart’s healthy. We had some great Guinness stew too
We went down to check out Glendalough monestary south of Dublin and visited the Johnnie Fox’s Pub (kind of a local landmark, with lots of high profile visitors including presidents, etc. Was a little touristy but had cool décor). The monastery was very nice, so were the small mountains.