Visit the former Nazi concentration camps at Auschwitz I and Auschwitz II-Birkenau on this 7-hour trip from Kraków. By June 1940, Jews and over 700 political criminals had been sent to Auschwitz and the atrocities had begun. Birkenau was built by Auschwitz prisoners and by October 1941 was used as an extermination camp. Between 1 and 1.5 million were killed, and approximately 90 per cent of those killed were Jews. Before Auschwitz-Birkenau was liberated in January 1945, the SS attempted to blow up the camp and destroy the documentation. They were only partially successful, and the Polish government decided to restore the site as a memorial to the victims.