Pope Francis walks alone through Auschwitz

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Free for once of his security entourage or cardinals, Pope Francis sat on a bench among the trees and bowed his head in prayer, remaining at length in silent contemplation before meeting Holocaust survivors.

Krakow. Pope Francis on Friday walked alone through the notorious wrought-iron "Arbeit Macht Frei" (Work Sets You Free) gate as he visited the former Nazi death camp Auschwitz-Birkenau.

Free for once of his security entourage or cardinals, he sat on a bench among the trees and bowed his head in prayer, remaining at length in silent contemplation before meeting Holocaust survivors.

"Lord, have mercy on your people. Lord, forgive so much cruelty," the pope wrote in a memorial book.

In front of the death wall where the Nazis executed thousands of people, he tenderly kissed former prisoners.

Among them was Helena Dunicz Niwinska, a 101-year-old woman who played the violin in the Auschwitz orchestra, as well as inmates who worked at the camp hospital or who were there as children.

"It was very moving," 86-year-old survivor Janina Iwanska told AFP.

"I wanted to kneel before him, but he took me in his arms and kissed my cheeks."

Fellow survivor Alojzy Fros, who is 99, still remembered his arrival at the camp.

"Just after I arrived, through an open door I saw naked bodies piled up like logs about a metre high," he said.

"I'll never forget it."

Francis lit a candle in front of the death wall before visiting the cell of Polish priest and saint Maximilian Kolbe, who died at Auschwitz after taking the place of a condemned man.

Francis cut a solitary figure as he knelt in the dark, underground cell where the priest was starved then executed.

The Argentine later lead prayers for the 1.1 million people who were murdered at the camp as part of Nazi Germany's "Final Solution" of genocide against European Jews which claimed six million lives in World War II. (AFP)