If you like non-touristy places, I would definitely recommend you to go to Bydgoszcz and Szczawnicza, but if you are ok with the fact that you will find a lot of tourists, I would recommend Zakopane and Mazury (not so touristy, its a bunch of lakes in the north of Poland, very pretty and not everybody knows about that). Hit me up if you wanna know anything else (: