World Youth Day is a large Catholic youth celebration inaugurated by Pope John Paul II in 1984 in order to create solidarity among Catholic youth on a worldwide level, and to galvanize the faith of the Church youth. It is celebrated every year at the local diocese level, and every two to three years as a huge week-long International Festival and religious pilgrimage. World Youth Day has been celebrated at many different locations internationally, including Rome, Paris, Buenes Aires, Toronto, and recently in August 2005, in Cologne, Germany

World Youth Day typically draws hundreds of thousands of pilgrims, or even several million, who come from virtually every nation in the world (generally in groups from their local parish or as volunteers) to worship God. I just returned from World Youth Day in Cologne, and there were over one million pilgrims. I met people from many different nations, and learned a lot about different cultures. It was also inspiring to hear the Holy Father speak in front of the impressive gothic Cologne Cathedral. WYD 2005 was an incredible experience, but World Youth Day can be stressful for people with claustrophobia or fear of crowds, as extreme crowding is typical of World Youth Day events.

A typical day of the World Youth Day week generally involves morning prayer, a catechetical session with a bishop from one's country (or atleast who speaks one's native language), and some sort of festival/party in the evening. Typically pilgrims will gather to trade various trinkets from their home countries, such as scarfs, tee-shirts, or flags. It is not uncommon to see a lot of nationalism or patriotism from various pilgrims at World Youth Day, but generally it is all benign.

World Youth Day involves the Pope coming to visit the youth for a talk, and for a final mass on Sunday morning, at a large gathering place. In WYD at Cologne in August 2005, the final mass was held at the "Marienfeld", about 15 km outside of Cologne, where Pope Benedict XVI celebrated mass with over one million parishoners, before everyone departed.

The next time World Youth Day will be celebrated internationally will be in Sydney, Australia in August, 2008.