Per request, based on a long trip in '99 and a short one in 2010 so may be a little dated.
  1. Stay at the Shelbourne Hotel in Dublin
    The best: best location, best bars, best concierge. They wrote the Irish Constitution here.
  2. Dublin is small
    It's not London or Paris. The casual traveler could move on after two days without much regret.
  3. Dublin: see if you can tour the crypts of St. Michans
    Only open by tour on a weird schedule, but truly cool if you're into the mummified bodies of Crusaders and such.
  4. Don't go to the Aran islands
    Unless you're really into the Irish language, this is a little bleak, overtouristed, and boring.
  5. Go to Dingle
    This is the Ireland you're looking for. The Dingle peninsula has everything: ruins, mountains, lakes, landscapes, country towns, even beaches. Dingle town has great pubs, cool shops, a famous friendly dolphin in the harbor, great music. From Dingle you can bike along the cliffs, past all kinds of ruins, up into pretty wild mountains, across to little villages - Ireland in awesome microcosm.
  6. If you're brave, go to Skellig Michael
    A harrowing boat trip and then a steep climb up exposed rock steps, but for my money the ruins of this 6th-8th century monastery is as dramatic and impressive as Machu Picchu. One of the coolest places I've ever seen that nobody's heard of. Take non-drowsy seasickness meds.
  7. Go to Kinsale
    Great town, a bunch of abandoned forts to scramble around on, prides itself on food
  8. Bike.
    Ireland's one of the best places to bike in the world. You might get a little rained on but the country roads are perfect for this.
  9. Walk.
    Ireland has a whole culture of walks and trails. Killary's a great one, with abandoned towns and trails on old roads along what's basically a fjord. Plenty more closer to Dublin. Get the Ordnance Survey maps that mark all the sacred wells and standing stones and all kinds of interesting weirdness.
  10. Go to a trout fishing lodge
    Out in the west there are a few spectacular lodges in 18th century mansions that cater to trout fishing. A guide takes you down some fantastic stream. Expensive but special.
  11. Cork/Cobh
    Good times. Cork's a neat city, Cobh's a cool old seaport, last stop for the Titanic
  12. Don't go to Blarney
    It's kind of dumb and kitschy. There are better castles, if that's what you're after.
  13. Look up anyone you might even kind of be related to
    Irish people are obsessed with genealogy and their own diaspora and will probably want to drink with you if you can find even the mildest connection