The Papal Basilica of Saint Paul Outside the Walls is one of Rome's four major papal basilicas, along with the basilicas of Saint John in the Lateran, Saint Peter's, and Saint Mary Major, as well as one of the city's Seven Pilgrim Churches. The basilica is the conventual church of the adjacent Benedictine abbey. It lies within Italian territory, but the Holy See owns the basilica and it is part of the Vatican's extraterritoriality.