Survivors of Auschwitz leave the concentration camp at the end of World War II in February 1945. Above them is the German slogan Arbeit macht frei, which translates to Work sets you free. Galerie Bilderwelt/Hulton Archive/Getty Images
The Soviet Army liberated the Auschwitz concentration camp in Poland on January 27, 1945.
About 7,000 prisoners were there when the Soviets arrived. Those people had been left behind — too weak or sick to move when Nazi officers forced nearly 60,000 prisoners to march west as the Soviets approached.
More than 1.1 million people were murdered at the Nazi camp complex.
Editor's note: This gallery contains graphic images. Viewer discretion is advised.
Identification photos of child inmates at the Auschwitz-Birkenau concentration camp were taken by Polish portrait photographer and fellow prisoner Wilhelm Brasse, who was ordered to document prisoners in the camp. Auschwitz consisted of three main camps: Auschwitz I, Auschwitz II (also known as Auschwitz-Birkenau) and Auschwitz III (also known as Auschwitz-Monowitz). De Agostini Editorial/Getty Images
This aerial photo shows the layout of the Auschwitz I camp in April 1944. AP
Prisoners of Auschwitz greet their liberators in 1945. Belarusian State Archive of Documentary Film and Photography/United States Holocaust Memorial Museum
An electrified fence surrounds one of the camps. RIA Novosti/Sputnik/AP
Corpses of women are piled up on the floor in February 1945. Stanisław Mucha/United States Holocaust Memorial Museum
This is the first page of a prisoners list that was prepared by hospital staff after the liberation. This page shows "kinder ohne eltern," or children without parents. Courtesy Memorial and Museum Auschwitz-Birkenau
Ivan Dudnik, a 15-year-old Russian, is rescued. The teen had been described as insane from the treatment he received from the camp. Sovfoto/Universal Images Group Editorial/Getty Images
A large pile of prayer shawls, confiscated by the Nazis from arriving prisoners, are seen stored in one of the warehouses in Auschwitz. National Archives and Records Administration/United States Holocaust Memorial Museum
Civilians and soldiers recover corpses from graves shortly after the liberation. Mondadori Portfolio/Getty Images
A few Auschwitz survivors stand by a fence as the Soviet Army arrived to liberate the camp. Galerie Bilderwelt/Hulton Archive/Getty Images
The ruins of gas chambers — blown up by Germans retreating from the Soviets — are seen in January 1945. Courtesy Memorial and Museum Auschwitz-Birkenau
Glasses of prisoners are piled up at the camp. Roger Viollet/LAPI/Getty Images
Child survivors show their arms, which has been tattooed by the Nazis. Galerie Bilderwelt/Hulton Archive/Getty Images
Bodies of prisoners were found covered in snow on the main street of the camp. Henryk Makarewicz/United States Holocaust Memorial Museum
Survivors stand behind a barbed-wire fence. Some of the children are wearing adult clothing they were dressed in by Soviet soldiers. Galerie Bilderwelt/Hulton Archive/Getty Images
Bales of hair from female prisoners, numbered for shipment to Germany, were found after the camp's liberation. National Archives and Records Administration/United States Holocaust Memorial Museum
Female survivors in the barracks at the camp. Hundreds of prisoners were housed in the crowded quarters. Galerie Bilderwelt/Hulton Archive/Getty Images
This train was loaded with the personal effects of Auschwitz victims. It was abandoned before it could make its trip to Germany. Some of the freight is scattered and buried in the snow. Stanisław Mucha/Instytut Pamieci Narodowej/United States Holocaust Memorial Museum
Soviet soldiers are seen with liberated prisoners. Sovfoto/Universal Images Group Editorial/Getty Images
Prosthetic limbs taken from executed prisoners are piled at the camp. AFP/Getty Images
An overview of the camp in 1945. Courtesy Memorial and Museum Auschwitz-Birkenaua
CaptionPrisoners gather a couple of days before the camp's liberation. RIA Novosti/Sputnik/AP
Nazi officer Karl Hoecker lights a candle on a Christmas tree only weeks before the liberation of Auschwitz. It is a page from an album that depicted activities in and around the camp. United States Holocaust Memorial Museum
Jewish men are lined up at the Auschwitz-Birkenau camp in May 1944. This photo is from a Nazi documentation of the events at the camp. United States Holocaust Memorial Museum
This picture shows prisoners' bodies being burned in the Auschwitz-Birkenau camp in August 1944. It was secretly taken by a Jewish prisoner who was forced to work in and around the gas chambers.Courtesy Memorial and Museum Auschwitz-Birkenau
Jewish prisoners wait in a clearing near a grove of trees before being led to the gas chambers in May 1944. United States Holocaust Memorial Museum
This undated photo, taken by a guard, shows female prisoners lined up for a hard labor assignment.AP
A Jewish woman walks toward the gas chambers with three young children and a baby in her arms in May 1944. United States Holocaust Memorial Museum
Bodies were brought up to this crematorium to be incinerated at one of the camps. Galerie Bilderwelt/Hulton Archive/Getty Images
Jewish women selected for forced labor stand at a roll call in front of the kitchen at Auschwitz-Birkenau in May 1944. United States Holocaust Memorial Museum
