The tower is 23 meters high, it was part of a castle that dominated the hill and had a signalling function. The hypotheses of its origins are controversial perhaps there was a building of the IV-VI century that controlled the Via Settimia (later called Via Francescia). In its present form, the complex was probably built in the third quarter of the 12th century, dating submitted on the basis of typological comparisons. It was a "castrum" and as such it is mentioned in various documents starting from the thirteenth century. At that time, it belonged perhaps to the Da Castello counts, who signed peace with the municipality Novara, in presence of the Bishop-Count. From 1235 it was firmly in possession of the bishops of Novara, with the function of guarding and signalling.
The statutes of the community of the Province San Giulio ordered that all valid men rushed to the arms at the sound of the tower bell. However it was added later, perhaps shortly after the construction of the roof, which took place in the 14th-15th century.