On the Old Town side of the river, on the river front is a stretch of cafes and restaurants. Always happy, always crowded, always fun. And even with the mad amount of people, somehow most of these places always find a way to seat you. It a higher kind of math. I would recommend Terreiro, Bacalhau, Fish Fish, Porto Escondido, Fiume Douro, Farol da Boa Nova, and the lovely Escama. Oh, no! I forgot Postigo do Carvão and Chez Lapin. Now you are good for more than a week at least.
Ribeira