Gdansk has incredible bars, probably one of the best places to go and just… do a bar crawl. My favourites (bear in mind this was five or so years ago) were Brovarnia, Flisak 76 (amazing amazing place), Loft, Browar Piwna… also loads of those bars where everything is 4 zloty (resulting in the phrase "4 zloty shotty!) which at the time I went was 80p, absolutely brutal scenes.
In Your Pocket would have a list of bars I reckon, and given the “craft” beer scene in Poland has got massive recently I bet there’s bloody loads of places to drink.
I remember having good pierogi and the best jacket potatoes ever at Bar Pod Ryba – srsly, just really good.
Make sure you go to Sopot on the train and walk along the pier. Josef K is a lovely little restaurant in Sopot and again, lots of little bars.
Go to the Solidarity Museum.
It was like -20 degrees when I went. Wrap up warm!
Edit: I love Flisak 76 so much that I named a Spotify playlist after it called something like “If I ever opened a bar it would be exactly like Flisak 76 and this would be the music I played…” 