Auschwitz II-Birkenau was a concentration and extermination camp that functioned as part of the Auschwitz complex during World War II. It was operated by Nazi Germany in occupied Poland.
The site is characterized by its extensive infrastructure, which included gas chambers used for mass killings during the Holocaust. While Auschwitz I served as the main camp (Stammlager) in Oświęcim, Birkenau functioned specifically as a concentration and extermination facility alongside other sites like the Monowitz labor camp.