Auschwitz-Birkenau or Auschwitz II was the largest camp within the Auschwitz camp system, and was the site of the killing centre and largest inmate population. It opened in 1940 and, from 1941, people were gassed there, first in two adapted buildings then later in four purpose-built gas chambers and concentration camps. Jewish people were deported from all over Europe to their deaths at Birkenau.
