Auschwitz-Birkenau, both a labour and extermination camp and the largest of all those constructed by the Nazis, has the highest death toll running between 1.1 to 1.5 million over 4 and a half years.
However, Treblinka disposed of 870,000 victims in far less time, taking just 16 months.
Belzec, another extermination camp, murdered 434,508 in just over a year, and of all the inmates that went through it's gates only two survived.