The answer to that question is relatively easy – plenty. You have a great opportunity for city sightseeing tours by day and pub crawling at night. In the very heart of the city, you will find so many attractions, event and opportunities you might not want to leave as you have initially planned.
What to do in Krakow by day? First off all you don’t want to miss on great monuments and building this city has to offer. It’s historical beauty is probably the best to look for in Poland. Old Capital of Poland is not only one of the oldest cities in the country, but it was also relatively well preserved during many wars. Therefore you can see royal castle, old market with their centuries-old buildings and monuments to great Polish people. You can take a short breaks in many cafes around main square and visit old Jewish district in the afternoon or next day for more.
What to do at night? Well possibilities are not scarce. First of all, you will find a lot of clubs that will open their gates during evening and will be visible with flashy lights and queues of people. On top of that you will find a lot of interesting activities on almost each street. One of such ideas is definitely Bad Axe club https://madaxe.pl/what-to-see-and-do-in-krakow/. Recently popular place, that will organize your afternoon or evening in true Viking theme. You can bring your own beer or drinks there and have fun in simple competition of throwing axes at target. It is easy and flawlessly works in any company. You can even take some pictures to commemorate this great event.