The image of Our Lady marks the spot where once the small holm oak stood over which the Virgin appeared for the first time to the little shepherds on 13 May 1917. This episode became known since then as 'The Miracle of Fátima'. The first Mass was there celebrated on 13 October 1921. The Sanctuary has received the papal visits of Paul VI, John Paul II and Benedict XVI, and is the main religious pilgrimage destination in Portugal, being the Mass celebrated at midnight of the 12th to 13th May, an all-time high. The whole area is covered by a vast sea of candles lit by pilgrims.