Krakow is an unbelievably cool city! On top of being really cool, the city is super cheap. A good meal in the main square with a drink will set you back under fifteen dollars. Public transport is a mere forty cents per ride. A huge recommendation of mine would be to take a day trip to Auschwitz. It is really easy to get to by either bus or train. The trip is worth it. Quickest tours take about 4 hours or so and it will take you well over an hour to get there so plan on most of your day for this trip.
Culture and experiences
This is where Auschwitz is located. A great day trip