 While it is neither the mother church of the Catholic Church nor the cathedral of the Diocese of Rome (these equivalent titles being held by the Archbasilica of Saint John Lateran in Rome), St. Peter's is regarded as one of the holiest Catholic shrines.It has been described as "holding a unique position in the Christian world" and as "the greatest of all churches of Christendom".Catholic tradition holds that the basilica is the burial site of Saint Peter, chief among Jesus's apostles and also the first Bishop of Rome (Pope).