The first major Nazi camp to be liberated was Majdanek, located in Lublin, Poland. It was liberated in the summer of 1944 as Soviet forces advanced westward. The previous spring, the SS had evacuated most of the Majdanek prisons and camp personnel. The evacuated prisoners were sent to concentration camps further west, such as Gross-Rosen, Auschwitz, and Mauthausen. As the Soviet troops approached Majdanek at the end of July, the remaining camp personnel hastily abandoned the Majdanek concentration camp without fully dismantling it.
Soviet troops first arrived at Majdanek during the night of July 22-23 and captured Lublin on July 24. Majdanek was captured virtually intact. At Majdanek, the Soviet troops encountered a number of prisons who had not been evacuated in the spring, mostly Soviet prisoners of war. They also encountered substantial evidence of the mass murder committed at Majdanek by Nazi Germans. Soviet officials invited journalists to inspect the camp and evidence of the horrors that had occurred there. Continue reading from the Holocaust Encyclopedia
The Liberation of the Nazi Concentration Camps (Friends of the National World War II Memorial)
Who Liberated the Nazi Concentration Camps and Extermination Centers? (World Jewish Congress)
Liberation (United States Holocaust Memorial Museum)
Concentration Camp Survivors Share Their Stories (Imperial War Museum)