The Valley of Elvo is a geographic area in the province of Biella, in Piedmont. It holds numerous churches, the main one being the Marian Shrine of Graglia, dating back to the 17th century. Located on the border with the province of Turin and the Aosta Valley, it creates the divide between the area of Biella and the Canavese, stretching along the river Elvo, in the western part of the province, at the foot of the Biella Pre-Alps and the peaks of Bo and Mars.