A few steps from Port Vell you find Restaurante Carballeira. A Galician restaurant. Galician restaurants have a reputation for being the best if you are looking for fish. I had Parillada y marisco, grilled seafood. Very delicious and something you definitely should indulge you if you are in Barcelona. It is not cheap, but reasonable prices. For the grilled seafood I had a very tasty fresh white wine from the south of Barcelona.
Where: Restaurante Carballeira, Carrer de la Reina Cristina 3, Barcelona