January 27, 2015 10:10 AM EST

Correction appended

Hundreds of survivors returned to the Holocaust’s most infamous concentration camp, Auschwitz, to mark the 70th anniversary of the camp’s liberation for what’s expected to be the last time.

World leaders, including the presidents of Germany and France, joined about 300 survivors at a commemorative event at the Polish site on Tuesday, the BBC reports. About 1,500 survivors returned in 2005; many of the remaining survivors, now elderly, were children and teens when they were held in Auschwitz.

French President Francois Hollande’s presence at the event comes in the wake of terror attacks in Paris, including an attack at a Jewish supermarket. Russian President Vladimir Putin did not attend Tuesday’s commemoration, though the Soviet army was responsible for liberating the camp in 1945.

The site opened as a museum just two years later, in 1947.

[BBC]

Correction: The original version of this story has been updated to clarify the location of the Auschwitz Nazi concentration camp

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