Question: What network of German Nazi concentration camps and extermination camps built and operated by the Third Reich was where Magda Spiegel was murdered?
Context: The Warsaw concentration camp (German: Konzentrationslager Warschau , short KL or KZ Warschau) was an associated group of the German Nazi concentration camps, including an extermination camp, located in German-occupied Warsaw, capital city of Poland.  Its main target was the Polish population of the city. Below is the list of subcamps of Gross-Rosen "Stammlager" complex of Nazi concentration camps built and operated by Nazi Germany during World War II.  The camps are arranged alphabetically by their Nazi German designation.  For the list of present-day locations in alphabetical order, please use table-sort buttons. Death marches (Todesmärsche in German) refer to the forcible movements of prisoners in Nazi Germany.  They occurred at various points during the Holocaust, including in 1939 in the Lublin province of Poland, in 1942 in Ukraine, and between Autumn 1944 and late April 1945 from Nazi concentration camps and prisoner of war camps near the front, to camps inside Germany away from front lines and Allied forces to remove evidence from concentration camps and to prevent the repatriation of prisoners of war. Kemna concentration camp (German: "Konzentrationslager Kemna, KZ Kemna" ) was one of the early Nazi concentration camps, created by the Third Reich to incarcerate their political opponents (ostensibly in protective custody) after the Nazi Party first seized power in 1933.  The camp was established in a former factory on the Wupper river in the Kemna neighborhood of the Barmen quarter of Wuppertal.  It was run by the SA group in Düsseldorf. Mittelbau-Dora (also Dora-Mittelbau and Nordhausen-Dora) was a German Nazi concentration camp located near Nordhausen in Thuringia, Germany.  It was established in late summer 1943 as a subcamp of Buchenwald concentration camp, supplying slave labour from many countries occupied by Germany (including Italian POWs and evacuated survivors of eastern extermination camps), for extending the nearby tunnels in the Kohnstein and for manufacturing the V-2 rocket and the V-1 flying bomb.  In the summer of 1944, "Mittelbau" became an independent concentration camp with numerous subcamps of its own.  In 1945, most of the surviving inmates were evacuated by the SS.  On 11 April 1945, US troops freed the remaining prisoners.  Around one in three of the roughly 60,000 prisoners who were sent to Mittelbau did not survive. Language of Nazi concentration camps refers to a common stratum created in various languages of inmates of Nazi concentration camps that described the notions unique to life in the camps and served as "lingua franca". Auschwitz concentration camp (German: "Konzentrationslager Auschwitz" , ] , also "KZ Auschwitz " or "KL Auschwitz ") was a network of German Nazi concentration camps and extermination camps built and operated by the Third Reich in Polish areas annexed by Nazi Germany during World War II.  It consisted of (the original camp), Auschwitz II–Birkenau (a combination concentration/extermination camp), (a labor camp to staff an IG Farben factory), and 45 satellite camps. This article presents a partial list of the most prominent Nazi German concentration camps set up across Europe during the course of World War II and the ensuing Holocaust.  A more complete list drawn up in 1967 by the German Ministry of Justice names about 1,200 camps and subcamps in countries occupied by Germany, while the Jewish Virtual Library writes: "It is estimated that the Germans established 15,000 camps in the occupied countries."  The concentration camps are not to be confused with the extermination camps which were designed and built exclusively to kill prisoners on a massive scale immediately upon arrival.  The extermination camps of Operation Reinhard such as Belzec, Sobibór and Treblinka served as "death factories" in which German SS and police murdered nearly 2,700,000 Jews either by asphyxiation with poison gas or by shooting.  Meanwhile, the concentration camps listed herein served primarily as detention and slave labor exploitation centers.  Most of them were destroyed by the Germans in an attempt to hide the evidence of war crimes and crimes against humanity; nevertheless tens of thousands of prisoners sent on death marches were liberated by the Allies afterward. Magda Spiegel (1887–1944) was a German contralto who was a member of the Frankfurt Opera ensemble and was murdered in the Auschwitz concentration camp.  The baritone Richard Breitenfeld, also of the Frankfurt Opera, shared the same fate. Gross-Rosen concentration camp (German: "Konzentrationslager Groß-Rosen" ) was a German network of Nazi concentration camps built and operated during World War II.  The main camp was located in the village of Gross-Rosen not far from the border with occupied Poland, in the modern-day Rogoźnica in Lower Silesian Voivodeship, Poland; directly on the rail-line between the towns of Jawor (Jauer) and Strzegom (Striegau).
Answer: Auschwitz concentration camp