This proud baroque cathedral overlooking the daily market on Vodnikov trg is dedicated to St. Nicholas, the patron saint of fisherman and boatmen who created a powerful guild in medieval Ljubljana. Building took place between 1701 and 1708, under the Italian architect Andrea Pozzo, who modeled it after the church of Il Gesù in Rome. The magnificent frescos on the ceiling of the nave are by the Lombard painter Giulio Qualglio and depict the transfiguration of St. Nicholas
and the persecution of Christians under Diocletian and Nero. In honor of Pope John Paul II's visit in 1996, new bronze doors were added to the church. The main door tells the story of Christianity in Slovenia, whereas the side door shows the history of the Ljubljana diocese.