The Fortress was built by Alfonso II d'Este between 1579 and 1586, and designed by Marc'Antonio Pasi, to defend Castelnuovo Garfagnana and the Este territory from the Republic of Lucca. The inhabitans of the area, the “garfagnini”, contributed to its construction with the large sum of 30,000 crowns.
The complex - with a wall of 1150 meters, seven bastions and two doors – included several dwellings. Remaining examples of the sixteenth century constructions are: the captain's house, the troops dwellings, the stone well and the casemate bastion.
The coat of arms of the Este family stands on the door.
The imposing mass of the Fortress probably discouraged the enemies, as the only siege we know is the French one, led by General Gaffard in 1706.
In 1805 Mont'Alfonso became part of the State Property of the Principality of Lucca and Piombino ruled by Elisa Bonaparte Baciocchi, Napoleon's sister. After only nine years it became again part of the Estensi family properties. It was then that it took again an important role in the community of Castelnuovo, being used as prison.
In the XX century it became the summer residence of the Italian-Scottish family, Bechelli, who transformed one of the buildings into a modern Art Nouveau building and ran the stronghold as a farm.
During the Second World War, the fortress was used as a shelter by several Jewish families, and later, before being abandoned by the Bechelli, it was inhabited by peasants until the Sixties.
The monument was bought by the provincial administration in 1980. Since 2000, the Province of Lucca has embarked on a restoration project aimed at the reconstruction of some existing buildings and the renovation of damaged ones, developed with the endorsement of the European Union, the Italian-French Cross-Border Maritime Programme, Tuscany Region, the Superintendence, the Apuane Alps Regional Park, the Municipality of Castelnuovo Garfagnana, the Gal and Mountain Community (the current Union of Municipalities).
According to a popular legend, the fortress is connected via an underground tunnel to the Rocca Ariostesca in Castelnuovo, a secret passage that, in case of a siege of the town, would allow citizens to take refuge within the walls. The center of Castelnuovo
can be reached through the Path of Ariosto, which, over the years, has been renamed as “lovers walk”.
