On the slopes of Mount Arci, in the upper part of the town of Ales, in the centre of Marmilla and famous for being the birthplace of Antonio Gramsci (1891), rises a scenic place of worship, the bishopric of one of Italy’s smallest dioceses. The Cathedral of Saint Peter apostle can be reached going up the stairway towards the baroque façade that dominates a spacious piazza. Two bell towers stand on either side connected by a balustrade porch with a central arch. The grandeur of the church and its three domes will surprise you: two of them cover the bell towers and the other the main dome, which at 36 metres high covers the nave and transept. The piazza is also home to the bishopric palace, a seminary and the Madonna del Rosario oratory.