San Gimignano is situated on a hill, whose highest point is occupied by the Rock of Montestaffoli. During the Middle Ages, when it was owned by the Bishop of Volterra, who ruled the surrounding land, this position of control over the surrounding valleys revealed all its importance. Near the fortress grew up an important market, thanks to the position of San Gimignano along the Via Francigena. The market allowed flourishing trade with other towns of Tuscany and also with the most prosperous cities in both North and South.

In 1353 two circles of walls were built for the safety of the fortress and in 1348 the Florentines, who in the meantime had taken over the town, gave to Montestaffoli fortress the military look we know today. The decline of the fortress followed the general decline of the city, which gradually lost importance when the flow of pilgrims moved on Via Francigena different branches.

His abandonment lasted at least until the twentieth century. Even today, the fortress has only its basic structure with walls, devoid of the rooms and the original setting. Nevertheless it has kept the charm of breathtaking views of the beautiful countryside surrounding San Gimignano.