Auschwitz was not the first Nazi concentration camp, but it was without doubt the most infamous. Although the concentration camp system had been in operation for seven years when Auschwitz opened on 14 June 1940, Auschwitz has come to symbolise the atrocities of the Nazi regime. There are several explanations for this, but one of the most valid is the enormous number of people murdered there - more than one million, brought in trains (usually cattle cars and freight wagons) from all parts of Europe, from as far away as Norway and Greece, the majority were murdered immediately on arrival.