A true gem!
Krakow is a wonderful city. While many other cities in Poland were destroyed during the war and rebuilt, Krakow still stands as it (mostly) originally was. The people are kind and the whole place is beautiful. Every corner you turn there is something else to be in awe about. Not to mention that Krakow is just down the road from Auschwitz.
Insider Tip:Get out to the Jewish Quarter on a weekend and drink! If you can go to Auschwitz by yourself (not with a tour group). Make sure you check when you do and do not need to book a tour guide as it can be confusing. But going on your own will allow you to see more and explore. For western cultures, the Zloty is very cheap making everything very affordable.