Auschwitz death camp survivor Barbara Doniecka, 80, who was registered with camp number 86341, holds up wartime photo of herself, as she poses for a photograph in Warsaw on January 12, 2015. Doniecka was 12 years old during the Warsaw Uprising when she was sent to Pruszkow camp. She was then sent by train to Auschwitz-Birkenau. #

The infamous German inscription that reads 'Work Will Set You Free' at the main gate of the Auschwitz I extermination camp on November 15, 2014 in Oswiecim, Poland. #

The 'long walk' leads to the gas chambers, a path taken by prisoners who were immediately selected for death after arriving by train at the Auschwitz II Birkenau extermination camp, on November 13, 2014 in Oswiecim, Poland #

Autumn leaves carpet 'The Little Wood' where prisoners were held waiting to enter the gas chambers at the Auschwitz II Birkenau extermination camp on November 12, 2014 in Oswiecim, Poland. #

A watchtower and a barbed-wire fence are pictured at the memorial site of the former Nazi concentration camp Auschwitz-Birkenau in Oswiecim, Poland, on January 25, 2015. #

German Chancellor Angela Merkel stands in front of an historic picture of the Auschwitz concentration camp as she gives a speech during the International Auschwitz Committees remembrance ceremony to mark the 70th anniversary of the liberation of the Nazi death camp on January 26, 2015 in Berlin. The International Auschwitz Committee (IAC) was founded by survivors of the Auschwitz concentration camp aiming to let the world know what happened in the concentration and extermination camp Auschwitz-Birkenau and to look after the interests of the survivors. #

From left: 79-year-old Miriam Ziegler, 81-year-old Paula Lebovics, 85-year-old Gabor Hirsch and 80-year-old Eva Kor pose with the original image of them as children taken at Auschwitz at the time of its liberation on January 26, 2015 in Krakow, Poland. #

Auschwitz death camp survivor Danuta Bogdaniuk-Bogucka (maiden name Kaminska), 80, poses for a portrait in Warsaw on January 5, 2015. Bogdaniuk-Bogucka was 10 years old when she was sent to Auschwitz-Birkenau camp with her mother. Bogdaniuk-Bogucka was part of Josef Mengele's experiments when she was in Auschwitz. After the war she met her mother again and they discovered they had both been at Ravensbruck camp at the same time, but they had not realized this. As the liberation of Auschwitz approaches its 70th anniversary this month, Reuters photographers took portraits of now elderly survivors. #

Auschwitz death camp survivor Jadwiga Bogucka (maiden name Regulska), 89, registered with camp number 86356, holds a picture of herself from 1944 in Warsaw on January 12, 2015. #

Auschwitz death camp survivor Jadwiga Bogucka (maiden name Regulska), 89, who was registered with camp number 86356, poses for a portrait in Warsaw on January 12, 2015. During the Warsaw Uprising in August, 1944, when Bogucka was 19, she and her mother were sent from their house to a camp in Pruszkow and then moved on August 12, 1944 by train to Auschwitz-Birkenau. They were liberated by the Red Army on January 27, 1945. #

Auschwitz death camp survivor Laszlo Bernath, 87, holds up a picture of his family, who were all killed in the concentration camp during World War Two, in Budapest on January 12, 2015. Bernath credits his father being a practical man with his survival of Auschwitz. He was 15 when they were taken but his father told him to lie about his age so that they would not be separated. Even while in the camp, Bernath had no idea about the gas chambers. #

Auschwitz death Camp survivor Jacek Nadolny, 77, who was registered with camp number 192685, poses for a portrait in Warsaw on January 7, 2015. Nadolny was seven during the Warsaw Uprising, when he was sent with his family to Auschwitz-Birkenau by train. In January 1945, the family was moved to a labor camp in Berlin. #

90-year-old Holocaust survivor Hy Abrams points at the word "Auschwitz" as he poses for a photo with a book that he carries with him everyday that documents all the different concentration camps he was held in during the second World War, in the Brooklyn borough of New York on January 15, 2015. In a little leather book, the kind some men use to list lovers, Holocaust survivor Abrams keeps the names that still haunt him: Auschwitz, Plaszow, Mauthausen, Melk and Ebensee. It has been 70 years since the Soviet army liberated the Auschwitz concentration camp in Poland, where Abrams was taken at age 20 by German Nazi soldiers and separated from his mother, father, brother and three sisters. #

Wooden bunks inside a destroyed barracks at the former German Nazi concentration and extermination camp Auschwitz-Birkenau near Oswiecim, Poland on January 19, 2015. #

A small selection of the personal photographs taken from prisoners as they arrived at the Auschwitz II Birkenau extermination camp are displayed on November 12, 2014 in Oswiecim, Poland. #

Thousands of eyeglasses that belonged to people brought to Auschwitz for extermination, displayed at the former German Nazi concentration and extermination camp Auschwitz in Oswiecim, Poland on January 19, 2015. #

Children's shoes confiscated from Auschwitz prisoners lie in an exhibition display at the former Auschwitz I concentration camp, now a museum, on January 25, 2015 in Oswiecim, Poland. #

Empty canisters of Zyklon B, the poison gas used to kill prisoners, displayed at the former German Nazi concentration and extermination camp Auschwitz in Oswiecim, Poland on January 19, 2015. #