The German police took Buergenthal and his parents to a location near Auschwitz, a concentration camp in Occupied Poland:

I was ten years old on that sunny morning in the first days of August 1944 when our train approached the outskirts of the concentration camp of Auschwitz. Actually, as we were to find out later, we were on our way to Birkenau, located some three or four kilometers down the road from Auschwitz proper. It was in Birkenau that the gas chambers and crematoriums had been erected, and it was here that millions of human beings died. Auschwitz proper was merely the public front for the Birkenau extermination camp. Auschwitz was shown to visiting dignitaries, whereas Birkenau was the last place on earth many of the prisoners sent there were destined to see (64).

Auschwitz was comprised of several camps. Men and women were in separate camps, and Buergenthal was separated from his mother immediately upon disembarking, unable to even say goodbye. Buergenthal and his father were placed together in camp E, known as the Gypsy camp because prior to their arrival it housed Gypsy families, all of whom were murdered. They were tattooed with their assigned numbers. Buergenthal was B-2930 and his father was B-2931: