The Firmafede fortress , also called Cittadella, is an imposing defensive structure on the edge of the city walls within the historic center of Sarzana.

During the 15th century the city became an important strategic point when Lorenzo the Magnificent decided to transform the village into a military stronghold of the Florentine lordship. The pre-existing fortification, built by the Pisans in the 13th century, was completely destroyed and rebuilt. In 1496 the fortress passed to the Banco di San Giorgio and from 1562 to the Republic of Genoa, remaining there until 1797. In the nineteenth century, with the annexation of the Republic to the Kingdom of Savoy and with the radical changes in defensive strategies, the fortress was first used as a police station and later as a prison until the 1970s.

Today the fortress, entirely restored, hosts exhibition spaces, festivals and cultural events. Since 2016, its spaces have also hosted the Museum of Fortresses (MudeF) which through an interactive and multimedia path tells the history and characteristics of Lunigiana through its fortresses, uses and customs, inserting them into their living and historical context.