According to U.S. organizers, this will be the largest delegation representing any country outside of Australia. Cardinal Francis George, archbishop of Chicago and president of the episcopal conference, is one of the prelates set to attend.
The youth are divided among some 1,140 groups of varying sizes, organized by dioceses, parishes, religious associations or schools. Some of the youth are going with their families.
The July 15-20 World Youth Day is the 10th international celebration since Pope John Paul II started the events in 1985.
According to the U.S. episcopal conference, for the first time at a World Youth Day, the conference will sponsor a Mass for all U.S. groups in Sydney. Cardinal George will preside and deliver the homily on Saturday, July 19, at an outdoor location in the center of Sydney.
U.S. youth will also have roles in other aspects of the Youth Day events.
Armando Cervantes from the Diocese of Orange, California, will be among 12 young adults who will have lunch with the Holy Father on Friday, July 18.
Juan Martinez from the Diocese of Austin, Texas, will receive the sacrament of confirmation from the Pontiff.
Annalee Moyer, from the Archdiocese of Washington, D.C., and Leonardo Jaramillo, from the Archdiocese of Atlanta, were selected to be part of the 200-member International Liturgy Group.
Meanwhile, across the Atlantic, some 2,000 young people from the United Kingdom will attend the youth event.
The Diocese of Westminster is preparing 170 pilgrims for World Youth Day. That group represents some 17 nations, including the Philippines, Croatia, Hungary, India, Lithuania, Nigeria, Poland, South Africa, Singapore and Zimbabwe.
David Burke, youth minister for the Diocese of Westminster, said: "It's great to see these young people representing the length and breadth of the diocese. The enthusiasm and anticipation is huge."
Archbishop Diarmuid Martin of Dublin will accompany some 200 pilgrims from that archdiocese to Sydney for the event.