Zyklon B gas cans

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The grounds of Auschwitz house a museum of relics where evidence of the Nazi crimes against humanity is preserved behind a wall of glass. Visitors from around the world come to bear witness and pay their respects.

A case filled with empty Zyklon B cans is a haunting reminder of the poisonous gas used by the Nazis for killing prisoners on a massive scale. "When the gas chambers were full, an SS man put on the gas mask, went to the roof, opened the little window there and threw such a can into the gas chamber," Professor Wiesel explains. "Unspeakable pain and horror—that's how they were killed. Mothers and children hugging. ... The death factory became industrialized and industry worked well."