Kelly's Cellars on Bank Street is one of Belfast's oldest pubs, a traditional Irish bar of low ceilings, stone floors, and dark wood that has changed little since the 18th century. It's a few streets back from the main tourist circuit and attracts a local crowd who come for the Guinness and the craic.
The pub has live traditional Irish music several nights a week, the quality of which is reliably good. On busy evenings, the bar overflows into the street. It's the most genuine traditional Irish pub experience in Belfast — less polished than the Cathedral Quarter bars, more interesting for it. Go on a Thursday or Friday evening when the music starts.