Dublin is a great 3 day getaway from Atlanta ! For cheap transportation from the airport to the city center, take the Aircoach bus for approx. 7 EUR. Look for the signs at the airport. Dublin is a wonderful “walking” city. Be sure to visit some of the great Irish Pubs in the Temple Bar area.
If you get a chance, visit Malahide Castle . Take the northbound DART to Malahide Station. The castle is within walking distance from the train station.
Enjoy!