Being on the train, the passengers already see pipes of crematoria, smoke, and fire. After leaving the train, Elie and his companions smell burning flesh. At this moment, their illusions that the Nazis cannot harm people and Auschwitz may be a good place are destroyed.
Detailed answer:
Living far from the horrors of war, the Jews of the small town of Sighet cannot believe in Nazi cruelty. They still deny the obvious fact that they are captives of a brutal regime even after the Nazis send them to an unknown destination. Everybody except a woman named Mrs. Schächter is looking for a reason for optimism. She, in turn, is haunted by visions of fire and furnaces. Passengers do not take her seriously until they see a crematorium pipe from the window. Only when the flames become visible, and Jews are finally scared.
They leave the train and feel the smell of burning flesh spreading from the crematorium and becoming stronger. This terrible smell accompanies the arrival at Auschwitz camp and forever crashes into the captives’ memory. In addition to crematoriums, in which the bodies of prisoners who died in the gas chambers are burned, there are also special pits of fires on the camp’s territory. Next to a similar one, Elie is standing when Dr. Mengele performs a selection. The arrived people are divided into two groups. One group will work hard. Another one will die immediately. Young children who cannot work are sent to this fire alive.