In one of your trips to Krakow, if you have time then you should definitely visit the Rynek Underground Museum. Its an Hi-Tech and highly popular museum that takes visitors four meters under the surface of the market square.
The subterranean excavation of the square began in 2005, after the discovery of various artifacts around Kraków’s famous Cloth Hall leading to speculation about what else might be found below street level. What was discovered was a treasure trove of items and structural remnants that paint a vivid picture of everyday commercial life in Kraków over the past 700 years, and even beyond.
Relying heavily on touch-screens and holograms, the museum highlights include a fascinating look into life before Kraków received its charter and the market square was laid out, displays on trade and transport in the city, a fantastic area for kids that includes a performance by automated puppets, and the remains of an 11th-century cemetery replete with ‘vampire prevention burials’
Though I was initially lost, having only a fraction of information about Krakow. But as you go around browsing the whole interactive museum, you might get the gist of all that it stands. So incase you get fascinated by the city, then do visit this one museum.