There are tragic events and moments in history that you do not really want to speak about. One example of such an event is Holocaust. But, despite the fact that it was such a tragedy, it is needed to speak about it to make sure that it will never happen again.
That is why we recommend all visitors to Krakow to visit Auschwitz, the concentration camp, to see what happened there and to feel the disgust that people often experience as they walk through the different camps and houses. Here you can see some pictures from the concentration camps, and if you want to join in on a tour to Auschwitz while in Krakow, you can read more about the trips and Auschwitz here.