Delegations from around the globe have come to the former Nazi-German death camp to remember its liberation by the Soviet Union's Red Army on 27 January 1945.
“Auschwitz is a testimony of what human nature is capable of,” Polish President Bronisław Komorowski said in an interview over the weekend.
The camp has become an international symbol of the horrors of war.
It is estimated that around 1.1 million people died at the camp. The vast majority of the dead were Jews. Other victims included ethnic Poles, Soviet prisoners of war, and members of Europe's Roma and Sinti communities.
Several participants in the commemorations have stressed that anti-semitism has not become a thing of the past.
"If you are a Jew today, in fact if you are any person who believes in the freedom of religion, freedom of speech, freedom in free expression, you know that like many other groups, we are once again facing the perennial demons of intolerance," Oscar-winning filmmaker Steven Spielberg was quoted by Reuters as saying. The Hollywood director is in Kraków for the commemorations.
Spielberg directed Schindler's List (1993) in and around the Polish city of Kraków. The plot revolved around the fate of Jews in the city's ghetto, and a German industrialist who tried to protect his Jewish workers.
Meanwhile, tech-giant Google has prepared an online museum so that people all over the globe can witness the events which took place at the camp, as well as background to some of the Polish-Jewish families which were eventually sent to their deaths at the hands of the Nazis.
Materials for the interactive presentations were prepared by the National Auschwitz-Birkenau Museum, the Polish History Museum, and other institutions around the globe.