A nun role-plays a confession at one of the confessional booths set up at Madrid's Retiro Park ahead of the World Youth Day meeting in Madrid August 12, 2011. Up to a million pilgrims are expected to attend the week-long event from August 16 to 21, according to the organizers, with the highlight being the Pope's August 18 to 21 visit. REUTERS/Andrea Comas (SPAIN - Tags: RELIGION SOCIETY ANNIVERSARY)