Dublin’s great advantage over most European capitals is that it is small. The historic centre is about two kilometres across, everything on this list is walkable, and you can cross from Kilmainham to the Docklands in half an hour on foot.
That means a weekend is not a compromise here in the way it is in Rome or Berlin. It is enough for the city, provided you book the two things that need booking and do not spend the daylight in a gift shop.
Book before you fly
Only two things genuinely need it:
Kilmainham Gaol — guided tour only, tickets released on a rolling window, and summer slots go within days. This is the single most common Dublin planning failure and there is no way round it on the day.
Trinity College and the Book of Kells — timed tickets, and the early slots sell out.
Everything else on this itinerary is walk-up.
Day one: the south side
9:00 — Trinity College. First slot of the day. The Book of Kells exhibition is about forty minutes; the Long Room is what you will remember. Then walk the campus, which is free and open — the squares, the campanile, the cricket pitch — and out the back gate.
10:30 — National Museum of Ireland, Archaeology. Free, five minutes away on Kildare Street, and the best museum in the country. The Bronze Age gold and the bog bodies are both on the ground floor. Ninety minutes.
12:15 — St Stephen’s Green and lunch. The Green is five minutes from the museum; eat around Drury Street or Fade Street rather than on Grafton Street itself.
14:00 — Dublin Castle. Take the guided tour, which is the only way into the undercroft — the Viking foundations and the black pool that gave the city its name. An hour and a quarter.
15:30 — the cathedrals. Christ Church is four minutes from the castle; give the crypt more time than you think, and find the mummified cat and rat. St Patrick’s is another five minutes south. If it is a weekday in term, choral evensong at St Patrick’s is free and is the better way to see it.
17:30 — Grafton Street and the lanes. The buskers are out by now. Turn off into George’s Street Arcade and Powerscourt.
Evening. Dinner around South William Street, then a pub. Not Temple Bar — the Long Hall, Kehoe’s, Grogan’s and the Stag’s Head are all within five minutes of it and cost half as much.
Day two: the west side and the north
9:30 — Kilmainham Gaol. Whatever slot you got. An hour and a quarter, and it is the most substantial thing you will do in Dublin. Dress warmly; the building is unheated.
11:30 — the Guinness Storehouse, or not. It is fifteen minutes’ walk east from the gaol. If you want it, this is when to go, and the Gravity Bar at the top genuinely is the best view of the city.
If you would rather not, walk the same route on foot through the Liberties instead — Meath Street, Newmarket, and a distillery tour at Teeling, which costs a third as much and puts you in a room with a person rather than a screen.
14:00 — lunch in the Liberties, then walk down Thomas Street and back toward the river.
15:00 — cross to the north side. The Ha’penny Bridge, then either EPIC on the docks for the emigration story, or Collins Barracks for the decorative arts and the 1916 collection, which is free.
17:00 — Stoneybatter and Smithfield. Twenty minutes west along the quays. Cottages, coffee, and Arbour Hill, where the executed leaders of 1916 are buried — free, almost always empty, and more affecting than anywhere else in the city on that subject.
Evening — the Cobblestone in Smithfield for a traditional session. Free, nightly, and the real thing rather than the amplified version.
If it rains
It will. The museums are all free and all indoors: Archaeology, the National Gallery, Collins Barracks, the Natural History Museum, the Chester Beatty Library in the castle grounds, which is one of the best small museums in Europe.
If you have a third day
Get out of the city. Howth is thirty minutes on the DART for a cliff walk and seafood, or Glendalough is ninety minutes by bus for a monastic city in a glacial valley. Both are covered in the day trips guide.
What to skip
The hop-on-hop-off buses. The city is two kilometres across and the traffic is bad; you will walk it faster.
A second cathedral if you are not interested in the first. Two is a lot.
Temple Bar at night, unless the noise is what you came for. Twenty minutes by day is the right dose.