In a special ceremony in Birkenau, also called Auschwitz II, they also heard from one of the survivors, Noah Klieger, about the Death March when some 15,000 died after Nazis fleeing the advancing Soviet army in January 1945 forced inmates still able to walk to march west in freezing weather. They remembered Jan. 27, 1945, when the Red Army entered the camp and freed the remaining inmates, mostly children and sick people.