By Catarina Demony and Miguel Pereira
LISBON (Reuters) -Waving their countries' flags and singing, hundreds of thousands of pilgrims from all over the world flocked to one of Lisbon's main parks on Tuesday to mark the start of the world's largest gathering of young Catholics.
"It's very emotional," said Brazilian pilgrim Vitor Goncalves, 25, as the event's opening Mass was celebrated at the Parque Eduardo VII. "Each person fought to be here and seeing all these young people together is very encouraging."
Hymns were played, prayers were said and Cardinal Manuel Clemente welcomed the pilgrims and thanked them for coming to the Portuguese capital. Pope Francis, the highlight of the World Youth Day event, will land in Lisbon on Wednesday morning to celebrate Masses and meet with youth groups and politicians.
Over 350,000 pilgrims have registered to attend but Portuguese authorities say more than 1 million are expected.
They have been arriving over the last few days and are staying in schools, gyms, fire stations and with families, with many planning to sleep in the open before the closing Mass on the riverside Parque Tejo on Aug. 6.
Huge stages have been set up at different locations, screens installed, and posters with the pope's face plastered across the city.
Francis, 86, is making his first trip abroad since having intestinal surgery in June and uses a wheelchair and cane.
The event is taking place at the peak of the summer, with temperatures forecast to hit around 30 degrees Celsius (86°F). Pilgrims were given hats and reusable water bottles to help cope with the heat.
The festival, which runs for nearly a week, is held every two to three years and was begun by the late Pope John Paul II in 1985.
The celebrations will take place against the backdrop of a sexual abuse scandal in the Portuguese Church. At least 4,815 people were abused, largely by priests, over the past 70 years, a commission investigating the issue said in February. Francis is expected to meet privately with abuse victims.
Australian pilgrim Andrew De Santos, 35, who had come to Lisbon all the way from Melbourne, said the sex abuse scandal in Portugal and elsewhere was "very disappointing," expressing hope that the next generation would be able to move on from "errors" of the past.
There have also been separate concerns over the cost of hosting the event in one of Western Europe's poorest nations.
(Reporting by Catarina Demony, Miguel Pereira and Pedro Nunes; Additional reporting by Patricia Rua;Editing by Bernadette Baum and Rosalba O'Brien)
