The Jubilee of Youth, one of the biggest events of the Catholic Church's current Holy Year, gets under way in earnest on Tuesday with a welcome Mass in Saint Peter's Square.
Rome Police Roberto Massucci said Vatican estimates that as many as one million young people would take part in the event were being proven right, with pilgrims from 146 countries coming to the Italian capital for it.
The Jubilee of Youth will culminate with a huge outdoor Mass presided over by Pope Leo XIV in Rome's Tor Vergata area on Sunday.
Participants started arriving on Monday and their presence could be felt in the city from the early hours of Tuesday.
Many were wearing the flags of their homelands, with the red-and-green of Portugal particularly prominent during this reporter's journey into work.
The pilgrims include 25 young people from the Latin Patriarchate of Jerusalem.
"I met them before they departed and I asked them what they expect from this experience" Father Ibrahim Faltas, the Custodian of the Holy Land, told ANSA.
"They told me that they are bringing the desire for peace of the young people of a land that has suffered for too long to the Jubilee of Hope.
"They expect the world to listen to the needs of young people who lack the essentials.
"They will join their voices with those of the friends they will meet to pray for peace and to still be able to hope for the future."
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