This place was originally inhabited by a group of Celts who chose it as a safe place to preserve their traditions, language and religion. There are two facts which point to this: the name of the town, Borgarello, is of Celtic origin (from brug = heath); the second is the irregular perimeter of the complex which is linked to the particular circulation of the water (today underground and channeled in pipes) which was typical of Celtic settlements. In the High Middle Ages the site was developed into a Christian monastery, probably a small community of nuns devoted to prayer and work in the fields. For the purposes of military defence it became necessary in the Middle Ages to build something more efficient than canals. This led to the construction of a fortified structure some traces of which still remain, some walls and the corner towers. In that period the place was the property of the Del Majno family, related to the Visconti-Sforzas, who were granted the lands by the Duchy in order to have trusted allies in position of such strategic importance. The complex was probably connected with the Charterhouse and other buildings by a system of underground tunnels. The Del Bove family, merchants and nobles took possession in the 16th century and they were responsible for the painting and decorations on the tower and the noble coat of arms bearing a dove. In the mid-19th century the Bono family took over and their descendents undertook renovation work and historical and artistic research on the site.