When you arrive in Krakow, Poland and get settled in your hotel, you can ask the front desk about tours. Most can sell tickets to any one of the several tours including the tour to Auschwitz – Birkenau concentration camps. You do NOT need to book the tours in advance.
Make sure you are at the tour pickup site at least a half hour before you are to be picked up and you know which tour operator to go with. The pickup points are at the numerous hotels around Krakow and are within walking distance from most of the hostels.
If you are not sure, ask. The Polish people are extremely friendly and helpful. There are many tours and the ones to Auschwitz leave twice a day from Krakow – at least during the summer months. The tours cost but admission to Auschwitz and Birkenau are free. The bus takes about an hour to get there. After touring Auschwitz, you get back on the bus and are taken to Birkenau which is only about three miles away.
If you go to Auschwitz in the morning, you can also take the afternoon tour to the Wieliczka Salt Mine or take a walk around the Wawel Castle – Both I highly recommend. Auschwitz is a must – it is a symbol of how evil people can be to others.
The tours are operated year round and admission to the museum / concentration camps are free. If you choose to drive, it’s about an hour from Krakow.