The first historical document that indicates the presence of a small church in the valley, called Orgials, is an act of agreement on the borders of Vinadio and Isola, drawn up on September 23, 1307, which names "the hospice of S. Maria di Brasca". It was a small chapel flanked by poor rooms for the hospitality of wayfarers and pilgrims. In a deed dated 21 February 1447 it appears that the hospice was administered by the parish priest of Vinadio with four councillors, two of whom were elected by the municipality. It can be noted the importance of the hospice, both civil and religious, given the composition of the administrative group; it was, in fact, a sacred place, for the reception of all pilgrims, and at the same time necessary for the economic development of trade in the place. The oldest evidence on the life of the hospice of S. Maria attested the presence of hermits who dedicated themselves to the service of wayfarers.
With the development of the church into a sanctuary, the administration stipulated an agreement with a stable custodian called "Randiere". His duties were established as follows: - to live at the sanctuary all year round;
A document of 1443 for the first time attests the new title of the church from now on called "S. Anna". The old alpine hospice was changing physiognomy becoming a characteristic sanctuary. The cult of S. Anna and S. Gioachino had spread in the West after the Crusades and to give strength to the new devotion also on site the popular tradition resorted to a presumed apparition of S. Anna to a shepherdess, Anna Bagnis, that would have happened on a rock between the pastures higher up the church.
In every ancient legend there is always a fund of truth
It is still possible to reach the so-called Roccia dell'Apparizione, a few hundred meters away from the Sanctuary, where the statues of Sant'Anna with Mary child and the shepherdess kneeling in prayer facing them are placed. With the passing of time, towards the 16th century, the church was becoming more and more a sanctuary, since it was no longer just a place of passage for merchants, but was becoming a place of prayer and devotion, a destination for devout pilgrims. It dates back to this period the rebuilding of the altar and the purchase of a painting on a wooden panel depicting the saint, unfortunately lost with the French Revolution. In 1619 the church managed to obtain a relic of Sant'Anna, which is still preserved in the silver arm that is on display in the church, near the altar.
The most significant stage in the development of the sanctuary was the construction of the new church, the present one, in 1680-81, with the animation of don G.B. Floris parish priest of Vinadio, helped by the Municipality and the pilgrims. The 17th century church was built slightly further down the valley than the old chapel. At that time there were already thousands of pilgrims. The growing fame of the sanctuary was abruptly interrupted for some years with the French Revolution, a period in which the church was also sacked, and then resumed in the nineteenth century with the influx of many faithful.