Mauthausen-Gusen concentration camp grew to become a large group of Nazi concentration camps that was built around the villages of Mauthausen and Gusen in Upper Austria.
Auschwitz concentration camp was a network of concentration and extermination camps built and operated by the Third Reich in Polish areas annexed by Nazi Germany during World War II. It consisted of Auschwitz I (the base camp); Auschwitz II–Birkenau (the extermination camp); Auschwitz III–Monowitz (a labor camp to staff an IG Farben factory), and 45 satellite camps.