Rocca di Cerbaia, Castle ruin in Cantagallo, Italy

Rocca di Cerbaia is a ruined castle at 400 metres on a hill above the Bisenzio, in the Carmignanello locality of the municipality of Cantagallo. It is built in filaretto of local sandstone, with traces of two wall circuits: the lower one holds the remains of a small medieval apse-ended oratory, the inner one a barrel-vaulted cistern and service rooms. At the centre stands the largely collapsed pentagonal keep, the Mastio, once much taller, with remains of windows and arrow slits.

Built probably at the start of the 12th century to guard the "strada di Lombardia", the rocca was granted in 1164 by Emperor Frederick Barbarossa to the Alberti counts. In the 13th century it was one of the strongholds in the struggle between Alberti feudal power and the rising commune of Prato. In 1361 Niccolò Aghinolfo degli Alberti, last count of Cerbaia, sold it to Florence, which fortified it and installed a garrison, disbanded during the 15th century.

Cunizza da Romano, daughter of Adelaide degli Alberti and Ezzelino II da Romano, lived at the Rocca in her later years; Dante places her in the Heaven of Venus in Paradiso. She drew up her will here in 1278, after which nothing more is heard of her. She probably died at the Rocca and was buried in the adjoining cemetery.

Access to the fortress is via hiking trail number 48 from CAI-Prato, which starts from the village of Carmignanello. Sturdy footwear and moderate fitness are helpful, as the path involves uphill walking over uneven terrain.

The pentagonal keep, largely collapsed, was probably rebuilt in the second half of the 13th century, its forms modelled on the Castello dell'Imperatore in Prato. Below the walls stands the Ponte di Cerbaia, and a ruined house at the foot of the rock is identified by a Florentine legend as the shepherd's hut where Dante sheltered after the Alberti counts refused him lodging on a snowy night in 1285.