A convent of cloistered nuns (Dominican nuns of the Angels) built in 1520, it was used as a prison from 1806 by Felix I and as a house of correction by Maria Luisa of Bourbon from 1815.
From October 1943, it housed numerous resistance fighters and in many cases their families were also held as hostages. From 5 January, Augusto Mancini, a philologist from the University of Pisa and president of the Lucca CLN, was imprisoned there for six months.
A memorable action took place on 23 August 1944, when Franco Bonacchi, commander of the town's PAS, penetrated it in broad daylight disguised as a party official and helped three partisans sentenced to death for the assault on the BN headquarters in Castelnuovo Garfagnana to escape.
In the post-war period, it was home to jazz musician Chet Baker, among others, who was arrested for drug use and detained from August 1960 to the end of 1961.