Hundreds of thousands of young Catholics poured into a vast field on Rome's outskirts Saturday for the weekend highlight of the Vatican's 2025 Holy Year: an evening vigil, outdoor slumber party and morning Mass celebrated by Pope Leo XIV that marks his first big encounter with the next generation of Catholics.

Leo arrived by helicopter as the sun set over the Tor Vergata field and immediately boarded his open-topped popemobile for long loops through the flag-waving, cheering pilgrims. They had already been partying there for hours, setting up campsites for the night as misting trucks and water cannons spritzed them to cool them down from the 85F temperatures.