Much like the rest of Italy, Rome is predominantly Roman Catholic, and the city has been an important centre of religion and pilgrimage for centuries, the base of the ancient Roman Religion with the pontifex maximus and later the seat of the Vatican City and the pope. Before the arrival of the Christians in Rome, the Religio Romana (literally, the "Roman Religion") was the major religion of the city in classical antiquity. The first gods held sacred by the Romans were Jupiter, the most high, and Mars, god of war, and father of Rome's twin founders, Romulus and Remus, according to tradition. Other gods and goddesses such as Vesta and Minerva were honoured. Rome was also the base of several mystery cults, such as Mithraism. Later, after St Peter and St Paul were martyred in the city, and the first Christians began to arrive, Rome became Christian, and the St. Peter's Basilica was first constructed in 313 AD. Despite some interruptions (such as the Avignon papacy), Rome has for centuries been the home of the Roman Catholic Church and the bishop of Rome, otherwise known as the pope.
Basilica of St. John Lateran, Rome's Cathedral.
Despite the fact that Rome is home to the Vatican City and St. Peter's Basilica, Rome's cathedral is the Basilica of St. John Lateran, located to the south-east of the city-centre. There are around 900 churches in Rome in total, aside from the cathedral itself, some others of note include: the Basilica di Santa Maria Maggiore, the Basilica of Saint Paul Outside the Walls, the Basilica di San Clemente, San Carlo alle Quattro Fontane and the Church of the Gesu. There are also the ancient Catacombs of Rome underneath the city. Numerous highly important religious educational institutions are also in Rome, such as the Pontifical Lateran University, Pontifical Biblical Institute, Pontifical Gregorian University, and Pontifical Oriental Institute.
The territory of Vatican City is part of the Mons Vaticanus, and of the
