BRZEGI (POLAND) - Pope Francis was set to celebrate mass Sunday with some 1.6 million pilgrims in a vast plain outside Krakow, wrapping up a emotionally-charged trip which took him to Nazi concentration camp Auschwitz.
Pope Francis holds a prayer vigil at Campus Misericordiae in Brzegi as part of the World Youth Days (WYD)
High-spirited teenagers, scouts, priests and families camped under the stars in the vast "Campus Misericordiae" (Field of Mercy) near the Polish city ahead of the final mass of a week-long Catholic festival.
They were preparing for the final mass, which some 1.6 million worshippers are expected to attend, according to Bishop Damian Muskus, general coordinator for the festival.
Hundreds of thousands of people had streamed to the grassy site Saturday with folding chairs, sleeping bags, umbrellas and sun-hats, amid warnings hours in the baking July sun could be broken with a rainstorm.
At the evening vigil, his main address to pilgrims, Francis chastised "drowsy and dull kids who confuse happiness with a sofa", urging them to get out and live life rather than spend it glued to smartphones.
Latin America's first pontiff had faced stiff competition at the start of his five-day trip with the memory of immensely popular Polish pope and saint John Paul II, but quickly made the festivities his own.
As he visited the death camp in Auschwitz, he warned that the cruelty seen there "did not end" with World War II.
The "world is at war", Francis said, but the way to "overcome fear" was to welcome people fleeing conflicts and persecution -- a message with particular resonance in Poland, which has taken a hard line against refugees.
- 'For all people in need' -
On Saturday he prayed for God to rid the world of the "devastating wave of terrorism".
"In these dangerous times, he is convincing people not to be afraid to open up," Polish pilgrim Kasia Czajka, 40, said ahead of the mass.
"While John Paul II was especially focussed on the young, Francis is for all people in need".
The head of the world's 1.2 billion Roman Catholics cracked joke after joke with youngsters gathered nightly beneath his window, cranking up the party spirit at an event dubbed "the Catholic Woodstock".
The medieval centre of Krakow has been overrun all week by flag-waving groups from China to Samoa and Mexico, who were entertained between masses with concerts, break-dancing and football matches.
But Friday was a day of mourning as Francis walked silently through the notorious wrought-iron "Arbeit Macht Frei" (Work Sets You Free) gate at the Auschwitz-Birkenau camp, where 1.1 million people were murdered.
Freeing himself from the imposing security laid on for his visit, Francis sat on a bench among the trees and bowed his head in prayer before meeting Holocaust survivors and Catholics who had helped save Jews.
"Lord, have mercy on your people. Lord, forgive so much cruelty," the pope wrote in a memorial book.
In a heartfelt appeal to the world's young, he said it was up to them to fight xenophobia and "teach us how to live in diversity, in dialogue, to experience multiculturalism not as a threat, but an opportunity".