This camp, only a few kilometers from Auschwitz, was a death camp as opposed to a concentration camp, which Auschwitz was. Virtually everybody sent here was put to death in the gas chambers. There used to be just one track at Birkenau, but in 1944, with news of the huge number of Hungarian Jews to be deported there (400,000-500,000 in the course of around three months), the rail facilities were expanded.