MONTALCETO, or MONTE ALCETO, a castle in the Valle dell'Ombrone, now destroyed, of which it remains standing:
The tower on the top of a mountain of the same name in the middle of an oak forest.
The church of Saints Sabino and Alberto di Montalceto, in the twelfth century was subjected to the parish church of Asciano, to which the Pope Alexander III was confirmed with many other churches in that area.
The hermitage of Blessed Albert, a Camaldolense hermit here in penitence and who became famous after his death, surrounded it in 1150.
At the time of Blessed Albert, the Lordship of Montalceto belonged to the branch of the Cacciaconti della Scialenga, which then took the title from a Count Barotu, lord of Castel Baroti near Armaiolo.
Moreover, the dynasty of Cacciaconti soon lost the lordship of Montalceto in favor of the
Republic of Siena; which from 1208 onwards installed a trustee there. Because of the resistance to the payment of taxes to the Republic of Siena and the insubordination of the population towards the dominant city, in 1274 Siena decreed the demolition of their houses and all sorts of fortresses that protected the village.
Therefore it is assumed that the tower, still existing on the top of the mountain, was rebuilt in the mid-fifteenth century.
In 1521 Montalceto was donated by the Sienese Republic, together with the annexed land, to the nobleman Niccolò Borghesi, whose descendants made good use of it for many years.
Once called casatra, Montalceto returned to the community of Asciano and then became the property of the nuns of S. Chiara di Siena. At the suppression of the Monasteries, in 1808, Montalceto with the annexed lands, passed to the State Property, which sold it to private individuals again. At the moment Montalceto identifies itself with a farm located on the slopes of the mountain to the south west