the birth and development of the village of Sant'Ambrogio were closely linked to the events of the overlying the monastery of San Michele della Chiusa, founded in the last decades of the X century on the top of Mount Pirchiriano, and the road of France, which logistical base and administrative assistance of the abbey.
The historical nucleus of the town is Piazza IV Novembre, where still today there are the remains of the first church of the village and of the dominant castle, placed along the trail that climbs to the Sacra di San Michele. The ancient medieval cells incorporated in the urban fabric modern, read along the via Antiche Mura with the curtain wall that clasped the village in an irregular quadrilateral pivoted between the church of San Giovanni Vincenzo and the cylindrical tower, while the two input ports opened astride the road of France.
The current church, built between 1760 on a project by Bernardo Vittone, internally presents numerous furnishings as the blades of the high greater than Milocco, a refined Via Crucis of Raptus and the seventeenth-century Ancona of the Rosary of Bernardo Lanino. The plant at the basilica with three naves of the church was originally directed toward the east, but beginning from the XII century the increased pastoral needs of the inhabitants with transfer from cells to St Ambrose of the relics of Saint Giovanni Vincenzo, blessed hermit of Monte Caprasio, induced to extend the Church and the construction of a large bell.
Upstream of the church at the beginning of the trail that leads to the Sacra di San Michele stands the Abbey Castle (1266) from the articulated succession of construction phases and reinforcements with bertesche and machicolation as it emerged in the course of the excavation campaigns carried out within the framework of the yard of restoration and transformation of the castle in receptive structure. The seat of the castellan of San Michele and the place of administration of justice, was also occasional residence of Abbots clusini.
The town center of trade in virtue of the presence of the ancient street of France, from the nineteenth century with the arrival of the railroad was developed thanks to the installation of the first factories of the Susa Valley, Cotonificio Brothers Bosio (1871). The complex comprises, in addition to production establishments, even homes for employees and Villa Neveux, the residence of the owners, today the municipal headquarters. The imposing industry is structured in four parallel sleeves with ample internal courtyards, in exposed brick with decorations in the lambrequin in wood on the flaps of the gutter typical style eclectic artistic of the epoch.
The patronal feast of San Giovanni Vincenzo takes place in November According to ancient rites followed by the confraternity of the Abbadia that carry in procession the relics of San Vincenzo. Among the events of the "Gustovalsusa", the Meliga Day with the exhibition market of craftsmen and local producers celebrates the handicraft productions typical of the country, the fragrant biscuit with a base of flour of corn, the doughs of meliga.