Indeed, the Chronicles of Antonio Cesena, written in 1558, reveal that the construction of the keep in Varese, which had a similar structure to that of Piagnaro, was carried out by Piccinino, who summoned the “magistri” [Niccolò Piccinino] responsible for building the keep in Pontremoli to come to Varese and construct a fortification there. Cesena’s account states: “He immediately brought from Val de Taro and Lunigiana demolishers and master builders, and had a large number of kilns built for lime, and had our tower in Varese built by those same master builders whom he had brought for this purpose, and who had recently built the tower of Piagnaro Castle in Pontremoli.” The structural model that unites the two works in Pontremoli and Varese finds ample references in European fortified architecture of the first half of the 15th century, particularly in the French “beak-shaped” towers of Issoudun (Indre) and Roche-Guyon (Val-d’Oise).

Underneath the keep, there is a small quadrilateral courtyard, bounded to the west by the late medieval curtain wall and to the south and east by a large building in an “L” shape, which is the result of merging multiple structures from different construction phases. On the west side, the building takes advantage of the existing curtain wall, which is equipped with a cylindrical flanking tower. The internal distribution characteristics suggest that this large building was originally used as barracks, as evidenced by some 18th-century floor plans. It is likely that the garrison of the castle, mentioned in a document dating back to 1431 and consisting of 25 men including crossbowmen and shield bearers, was housed in these areas.

According to tradition, the ground floors of the complex housed the prisons, and in these rooms, the primitive sanitary facilities, known as “necessari,” are still well preserved today. The structure also preserves evident traces of our century, especially in the upper floors, when schools and residential apartments were created inside.

Leaving this space you have access to another courtyard, larger, through a paved ramp surmounted by a portal, built in the mid-eighteenth century. On the northern side of the courtyard, there is the chapel, which underwent renovations, probably in the 18th century. On the western side, there is a long building arranged on two levels. Along with the keep, this building represents one of the oldest structures of the castle and currently houses the Museum of Stele Statues. The openings facing the courtyard show signs of alterations and renovations, while near the chapel, on the first floor, there is a Gothic arch with a blocked opening. Il portale suggerisce una datazione risalente ai secoli XIV-XV. The main entrance to the castle leads, through an entrance hall, into this building, from which it is possible to enter the courtyard directly via a vaulted corridor. An emphatic stone decoration adorns this passage.

The courtyard, which houses a sandstone well, is bordered on the southern and eastern sides by a curtain wall with a walkway, which has eighteenth-century renovations. The base of the curtain, with shoe, was built with a precise masonry technique not unlike that used in the construction of the keep. This structure too could have been built by Piccinino, although there is an addition on the eastern side, including a defensive structure with a corner guardhouse, probably dating back to the 18th century.

In the seventeenth and eighteenth centuries the defenses of the castle were reorganized and studied to resist assaults from various directions. As in most complex fortified works, the fortress is divided into defensive structures defined, according to custom, with the names of saints. Eighteenth-century plans indicate the “Opera di San Giuseppe” to the north, adjacent to the keep, while the south-east corner is defended by the “Bastione di San Cosimo”; finally, guarding the western front, is the “Opera di San Giovanni Battista”.

The overall image of the castle, always vigilant over the city, is still today characterized by the grayness of its stones and the piagne, stone slabs used in the roof which, according to tradition, have given the castle the name of Piagnaro. Specific studies have not yet been conducted on the origin of the toponym, but we know that the fortification is already mentioned in the Annali Ghibellini Piacentini of 1262 as “planele” and in 1329 in the Annali Parmensi as ” fortilitia que dicitur Pianorium”. According to the historian Manfredo Giuliani, the origin of the toponym derives from the nature of the rock in place, used for the construction of the roofing slabs. The history of the castle structure is closely connected to the military events suffered over the centuries, characterized by continuous demolitions and reconstructions; specific studies and researches will perhaps be able to favor the knowledge of the modifications that have taken place over the centuries.

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Taken from ‘N. Gallo – Guida storico-architettonica dei castelli della Lunigiana toscana – Istituto Valorizzazione Castelli, Prato 2002.