SYDNEY, Australia—A massive Catholic youth celebration kicked off Tuesday with an Australian “G’Day” and a welcoming text message from Pope Benedict XVI to the tens of thousands of pilgrims who have traveled here from around the world.

As the clock struck midnight, a giant countdown clock ticked over to read “G’Day Pilgrims” — Good Day Pilgrims — drawing wild cheers from flag-waving youth who had gathered at St. Mary’s Cathedral to mark the start of the six-day celebration.

Registered pilgrims received the first of daily inspirational text messages from the pope: “Young friend, God and his people expect much from u because u have within you the Fathers supreme gift: the Spirit of Jesus - BXVI.”

Organizers say nearly 250,000 people have registered for World Youth Day, more than half of them from overseas.

The pope, who arrived Sunday, is resting at a secluded retreat on the outskirts of Sydney until Thursday, when he starts a busy round of meetings, takes a cruise on Sydney Harbour, and makes a major address to the pilgrims. The festival culminates with a papal Mass on Sunday.

On Monday, pilgrims bore a giant wooden cross through the streets of Australia’s largest city with thousands of faithful crowding around.

The 12.5-foot cross and a copy of a painting portraying Mary and Jesus landed by ferry at Sydney’s busy Circular Quay, completing a yearlong tour of more than 400 communities across Australia from the desert Outback to the tropical north.

Hundreds of faithful gathered on the wharf burst into applause and belted out Australia’s unofficial anthem, “Waltzing Matilda,” as the boat docked and the cross was carried into downtown Sydney.

“It means everything to me — it’s the symbol of my faith,” said Linda Wilkins, 55, a Sydney office worker who raced down from her high rise and ducked under a tape meant to keep onlookers away to caress the cross. “To touch it makes me feel I was an integral part of it.” During the procession, groups of volunteers took turns carrying the 88-pound cross and 33-pound painting. Pilgrims sang “Amazing Grace” and shouted out Australia’s rallying cry: “Aussie, Aussie, Aussie! Oi, oi, oi!” Others echoed with, “Holy, holy, holy! Spirit, spirit, spirit!” Stephanie Luna, 18, from Laredo, Texas, was one of many who burst into tears.

“We’re homesick and we’re exhausted, but it’s a sacrifice,” said the 18-year-old, who helped carry the cross through Sydney. “It was so beautiful.”

Benedict’s predecessor, John Paul II, gave the cross to the youth of the world in 1984 to be carried across continents as a symbol of Christ’s love for humanity.

Benedict has raised expectations that he will apologize directly to victims of past clergy sexual abuse while in Australia, telling reporters he will do everything possible to achieve “healing and reconciliation with the victims.” Activists in Australia have demanded a formal apology from the pope. Sydney Archbishop Cardinal George Pell, who met briefly with Benedict on Monday, said the church in Australia had apologized to clergy abuse victims a number of times, and was still struggling to help them heal. “That’s the most important thing. Counseling, help, justice,” Pell said.

Benedict also signaled he will discuss the need to face up to the “great challenge” of caring for the environment, noting that global warming is an issue worrying many young people.

There was a minor security scare at Benedict’s retreat late Monday, when a police officer in a guard unit accidentally set off what authorities described as a “distraction device,” seriously burning his hands. Deputy Police Commissioner Dave Owens said the pope was never in any danger.