Monteaperti is a locality in the municipality of Castelnuovo Berardenga known for the famous battle in 1260 fought between Siena and Florence in the plain of the Arbia and Malena streams. Both republics wanted to expand their hegemony over the territory, given the commercial and mercantile growth they were experiencing. Economic rivalry soon translated into political rivalry, as Siena was of Ghibelline supremacy, while the other, politically, was Guelph. After several warnings the final clash took place on September 4, 1260 with the final victory of the Sienese over the Florentines. The battle was tremendous, as Dante reminds us in Canto X of the Inferno in the Divine Comedy.
“Lo strazio e 'l grande scempio che fece l'Arbia colorata in rosso, tal orazion fa far nel nostro tempio.”
A commemorative pyramid has been placed to recall this event, and every year the Monteaperti Past and Present Committee organizes a torchlight procession to the Cippo di Monteaperti.