Rocca Fregoso of Sant'Agata Feltria

It is located on the Sasso del Lupo or Pietra Anellaria (from sandstone) and from the top of this natural overhang it dominates the Savio valley below.
The fortress was probably built around the year one thousand by the Cavalca family of the counts of Bertinoro, who at the time dominated the territory by ecclesiastical investiture.
Around 1100 it was enlarged by Altruda Frangipani, also from the Cavalca family, who managed the town with justice and wisdom
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Once the Counts of Bertinoro were extinct... the Rocca belonged to the Archbishops of Ravenna and, later, to the Faggiolani, the Guidi, the Tarlati, the Brancaleoni, the Malatesta and the Montefeltro.
And it is precisely with the advent of this last family that the primitive fortress underwent its first radical transformations.
... it is the first change from a war bastion to that princely residence that it will become with the Fregoso family.
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In 1660 S. Agata and its castle returned under the dominion of the Church.
Since then the fortress continued to be used as a residence at least until 1781 when it was transformed into a convent; on this occasion the conventuals built the church dedicated to San Francesco della Rosa, leaning against the fortress.
In the last two centuries the Fortress has been used as a Convent of the Conventual Friars Minor, as a high school, as a prison, as a Magistrates' Court and finally as a civil residence.
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Today the Rocca is managed by the Pro-loco Association and is home to the permanent "Rocca delle Fiabe" museum.(Source: roccadellefiabe.it/rocca-fregoso )

The Rocca Fregoso is a fortified construction located in the village of Sant'Agata Feltria, in the province of Rimini, Emilia-Romagna, Italy. The fortress dates back to the 10th century, but its definitive construction is attributed to the famous architect Francesco di Giorgio Martini. From 1474 to 1660, the fortress was the residence of the Fregoso family, originally from the Republic of Genoa and closely related to the da Montefeltro, dukes of Urbino. The fortress has been restored and well preserved and can be visited.