A sea of red and yellow flooded the streets of Sydney today as pilgrims wearing their WYD backpacks roamed the city to attend today's World Youth Day events.

30 students from Marist College, Penshurst students were among the pilgrims gathered for a Mass led by Bishop Christopher Saunders from Broome. 

WYD Co-ordinator Sharyn Blake said that the enthusiasm of the students was uplifting. "They are having an amazing time, exchanging koalas, flags and greeting pilgrims from different parts of the world."

Caroline Matti, a Year 11 student from Mary MacKillop College at Wakeley, was one of those selected to quiz Bishop Christopher Saunders in a question-and answer session on faith before the Mass.

Later in the day Bronx-based rapping priest Fr Stan Fortuna took to the stage for a free outdoor concert for thousands of enthusiastic pilgrims ranged along world-famous Bondi Beach.

On Tuesday about 150,000 pilgrims had been inspired by the spectacular Opening Mass held at Barangaroo at sunset.   Elias El Tarraf, a Year 11 student from La Salle Catholic College at Bankstown, said the atmosphere was beautiful, especially with Cardinal George Pell leading the Mass.

"It was extraordinary to see how the Catholic youth of the world came as one to worship God," he said.

"The Opening Mass had a spiritual effect on my faith and the faith of all the youth."

Elias was particularly touched by the different languages spoken through the Mass. "It brought everyone together as one," he said.