Plaza del Pósito is a pleasant little square in the newer part of the Casco Viejo, just before you get up to the cathedral area. Map here.
There are several bars and taperias around the plaza and in the nearby streets. My favourite is…
El Pato Rojo (Elementary A) 12 Calle Bernabé Soriano
‘The Red Duck’ is a boisterous marisqueria that’s buzzing at the weekends (you ‘ll be lucky to get a seat).
I come here in the week when I want to eat seafood.
The quality is pretty good.
Dean Bar (Intermediate B), 2 Plaza Dean Mazas (next square down the hill)
I like the music here (soul, funk) so I sometimes drop in for a night cap. You can sit out on their terrace in the square too.
They have a selection of about thirty rums and twenty gins but only two Spanish brandies, which is a good indication of current drinking trends in Spain.