The Monteriggioni Castle is located on the summit of the Mount Ala, because the the so-called podestà Guelfo da Porcari wanted to dominate all the Sienese territory, especially because he wanted to gain control over the Staggia valleys and both the Via Cassia and the Elsa, some very important streets going directly to Florence.
Even if the fortress was built between 1213 and 1219, nowadays it still preserves its link with both history and culture, having its elliptically-shaped boundary wall and its 15 towers.
As you can easily image, the object of contention between Siena and Florence was the total control of the area, and actually the city of Florence took Monteriggioni under its power.
The well known Italian author Dante Alighieri, who was from Florence, wrote about this castle in the Divine Comedy. The first time while conveying the size of Nembrotto, Fialte and Anteo, the three giants chained in the eighth circle (the one of the malebolge) in the Inferno, canto XXXI.
Actually the poet mistakes them for the towers of a fortified city, writing “for just as on the encircling wall Monteriggioni is crowned by towers, so upon the rim which encircles the well”.
The second reference can be found in Purgatory, canto XIII, where Dante describes the battle of Colle di Val d’Elsa in 1269, during which the Sienese took refuge in the fortress, which was unconquered by their Florentine enemies.
We can read the words spoken by Sapia Salvani, the aunt of the Sienese general: “my fellow citizens near unto Colle were joined in battle with their adversaries, and I was praying to God for what he willed”.
This castle is really important in Tuscany because of all these historical episodes happened during the 13th century, underling the extremely big power the city of Florence gained against Siena.