The Dirty Onion is a hugely popular bar in the Cathedral Quarter, set in one of the oldest buildings in Belfast with a vast, atmospheric timber-framed courtyard that buzzes on warm evenings and weekends. Known for its lively traditional music, craft drinks and the acclaimed Yardbird rotisserie upstairs, it draws a big, cheerful crowd. Combining historic character with a fun, energetic party atmosphere at the heart of the city’s nightlife district, it is one of the best spots in Belfast for live music and a spirited night out.