May 1944. A railway spur now runs inside the camp at Birkenau so the trains can stop beside the gas chambers. On the ramp an SS doctor looks at each person for a moment and points. Most are sent to buildings disguised as showers and are dead within hours.
Why then
Auschwitz opened in 1940 as a camp for Polish prisoners; from 1942 its Birkenau section killed Jews from all over Europe. By 1944, with Treblinka, Sobibor and Bełżec closed, it is the largest left. Hungary's Jews survived until Germany occupied its ally in March 1944.
What they wanted
Himmler and Eichmann want Hungary's Jews dead before the war is lost; Hungarian gendarmes do the rounding up. Prisoners forced to work the crematoria smuggle out photographs and rise in revolt in October.
What changed
In eight weeks some 430,000 Hungarian Jews are deported, most of them here. Around 1.1 million people are murdered at Auschwitz, about a million of them Jews. When the Red Army arrives on 27 January 1945 it finds some 7,000 prisoners; the rest have been marched west.
Still argued
Could Allied bombers have hit the railways or the gas chambers, and would it have saved lives? That argument is real. The facts of the camp are not; its killers, its survivors and its liberators all recorded them.