The Rocca di Vernio, or Fortress of Vernio, is 350 meters above Prato and is easily reachable via a road that leads to the fortress from the Sasseta area. However, the original access to the fortress (which is still open) is along a medieval path that leaves from San Quirico, near Casone, and heads up towards Poggio di Mezzana.
The fortress belonged to the Fief of Vernio, first under the Alberti Counts and later under the Bardi, a family of well-known Florentine merchants. The castle was originally a vast, well-structured building with strong defences. These defences, however, were destroyed in a series of battles that afflicted Vernio in the 14th and 15th centuries.
The ruins are still visible and offer an ideal view of the enormity of the original complex. The medieval settlement which provided homes for the local serfs has been well preserved, as has the Chapel of Saint Agatha. In the 1600s the Bardi moved their seat of power to the more comfortable and elegant Casone in Piazza di San Quirico.
The Fortress is private and has recently undergone significant restoration. Arrangements for visits must be made directly with the owners.