Pope Leo XIV presided over a final mass in Rome for over one million young people on Sunday, the culmination of a pilgrimage that has drawn Catholics from across the world.

"Aspire to great things, to holiness, wherever you are. Do not settle for less," Pope Leo told the crowd.

The week-long "Jubilee of Youth" -- a highlight of the Jubilee holy year -- was an enormous undertaking for the Vatican, with a half a million young pilgrims in Rome for most of the week.

On Saturday night, before a twilight vigil led by the pope, organisers said there were 800,000 people in the vast, open-air space on Rome's eastern outskirts, and on Sunday the Vatican said that number had grown to one million.

Most of them spent the night in tents, in sleeping bags or on mats in anticipation of Sunday's mass.

Among them was New Yorker Christofer Delano, who said he was "so happy to see Pope Leo" but stunned by the crowds.

"I didn't expect to see all these people. I knew there was going to be a lot of people -- I........

© International Business Times