A death camp camp is a concentration camp with special apparatus especially designed for mass murder. Six such camps existed: Auschwitz-Birkenau, Belzec, Chelmno, Majdanek, Sobibor, and Treblinka. All were located in Poland.

Auschwitz-Birkenau became the killing centre where the largest numbers of European Jews were killed. After an experimental gassing there in September 1941 of 850 malnourished and ill  prisoners, mass murder became a daily routine. By mid 1942, mass gassing of Jews using Zyklon-B began at Auschwitz, where extermination was conducted on an industrial scale with some estimates running as high as three million persons eventually killed through gassing, starvation, disease, shooting, and burning.