Pope Benedict XVI waves to the crowd at his arrival at the Cuatro Vientos Airport for the closing ceremony of the World Youth Day 2011 on August 21, 2011 in Madrid, Spain. Initiated by Pope John Paul II in 1985, World Youth Day youth-oriented events for the celebration of the Catholic faith are held every three years in a different country; this time in Madrid from August 16th to 21st, 2011.