Hundreds of thousands of young Catholics—organisers said close to one million—from 146 countries converged on Rome’s Tor Vergata field on Saturday for the climax of the Catholic Church’s Jubilee of Youth, the largest gathering to date in the pontificate of Pope Leo XIV. The meeting forms part of the 2025 Holy Year, which the Vatican says has already drawn about 17 million pilgrims to the city since late 2024. Arriving by helicopter and touring the crowd in his popemobile, the first U.S.-born pope urged participants to “seek justice in order to build a more humane world,” telling them that “friendship can change the world” and that society “needs missionaries of justice and peace.” Leo answered questions in several languages, warning of the commercial pressures of social media and encouraging the youths to ground relationships in faith. The vigil unfolded under heat of around 30 °C, with water cannons and misting trucks deployed to cool the crowd. Authorities mobilised roughly 10,000 police and civil-protection staff for the two-day event, which will conclude with a papal Mass on Sunday morning. The celebrations were marred by the death of an 18-year-old Egyptian pilgrim from cardiac arrest; the pontiff met privately with her companions and offered prayers. Many attendees planned to camp overnight on the 50-hectare site to secure a place for the concluding service.