Near the Cella Vecchia farmhouse lie the remains of Santa Maria, a Benedictine “cell” dependent on the Abbey of San Silano in Romagnano Sesia. Consecrated by Bishop Litifredo in the early 12th century (1123-1151), it is one of the few surviving foundations of that period. Today, all that remains of the ancient monastery is the imposing main apse of the original church, which was reduced to a rural structure over time. The apse interior is decorated with a series of 15th-century frescos from the Novara School, attributed to Maestro del Cristo della Domenica. Worthy of note is the figure of Christ Pantocrator enclosed within a mandorla, wearing a monastic habit with a leather belt and surrounded by the symbols of the evangelists. The upper register features the twelve apostles and a “Nursing Madonna”, albeit in a deteriorated state. Interesting details include ampoules for the religious service and a painted book beneath the window, indicating the space’s original liturgical function. Despite their poor condition, the frescos display a dynamic late-Gothic composition, which reflects the Benedictine outpost’s spiritual importance for those travelling between Proh and Castellazzo Novarese.