According to popular tradition, on 16 July 1480, the day of the Carmine festival, two shepherd children from the county then belonging to the Pepoli lords of Bologna - Donato Nutini and Cornelia Vangelisti, natives of the place - had a vision of the Madonna, who appeared at the Rio Davena ( confluence point of the two streams Tanone and Butrione, hence the name of the locality Boccadirio), which predicted for them a life consecrated in religiosity. Thus it was that the population of Baragazza decided to build a small church with a tabernacle dedicated to the Blessed Virgin of Graces in the 16th century. Again according to tradition, it is to Sister Brigida that we owe the acquisition of the image of the Virgin of Graces, a work from 1505 by Andrea Della Robbia, preserved on the main altar of the sanctuary, which since 1947 has been managed by the congregation of the priests of the Sacred Heart of Jesus. The sanctuary is for this reason the object of particular veneration by the people of Prato.