There are rumors telling that the first oratory in the place where now stands the Sanctuary was built already in 1161. When St. Charles came on a pastoral visit in 1579 he found the building of the first church of St. Valeria in poor condition, so he ordered to demolish a part of the porch and build on the remaining part a sacristy for storing the furnishings of the church. The works were not carried out and the Cardinal Federico Borromeo repeated the order, but again in vain, because of the rise of the famine and then the plague in 1630.
Only in the mid of the century the old building was demolished in order to build a more worthy temple, then the construction of a new sanctuary began, and it was opened three years later in 1653. Later in 1839 the church interior was decorated with two frescoes by Luigi Sabatelli.
The three-bell tower, visible from far away, was added in 1881; in 1932 the old church was demolished giving way to the Sanctuary as it is today: a Latin cross plan with three naves, with a total area of about one thousand square meters. On the main altar, in a triptych of gilded wood, stands the original image of the Virgin.
The Sanctuary is one of the stops of the Way of St. Augustine.