Dublin is a great city for a long weekend trip. Otherwise, rent a car and explore more of the country. If you stay in Dublin though, I would recommend the combo pass you can get at the airport. It's part Hop On/Off Bus as well as working with the public buses. The Hop On bus is a good one to do here. Some cities, it's not worth the price, but here in Dublin, I thought it was. Visit the Jameson Whiskey and Guinness Factories. We stayed outside the downtown area, but right near a bus stop. It worked out perfectly and saved us some cash.