The Papal Basilica of Saint Peter or officially known as "Basilica Papale di San Pietro en Vaticano" is the "mother church" of the Catholics and is regarded as one of the holiest Christian sites and place of pilgrimage. It is located within Saint Peter's Square at the Vatican city in Rome. The largest church in the world with the tallest dome, it has a 218-meter nave and 45 altars inside. It is the burial site of Saint Peter - the first Pope and one of Jesus Christ's twelve apostles. It is believed that Saint Peter's Tomb is directly below the altar of the basilica. On the underground of the basilica is the Vatican Grotto where the tombs of popes and some royalties were laid. The most recent was that of Pope John Paul II in 2005. (Rome, Italy / 2009)