Rocca Ariostesca is the symbol of Castelnuovo di Garfagnana, it dominates the central Piazza Umberto I and owes its name to the poet Ludovico Ariosto who lived there, from 1522 to 1525, as governor of the Este province of Garfagnana.

A small garrison already existed on the spot in the 10^th century, but the original structure of the fortress dates back to the 12^th century; modified throughout the 13^th century, it was significantly enlarged in the early 14^th century by Castruccio Castracani, who led to an enlargement of the entire walls of the village; later Paolo Guinigi ordered the construction of the imposing tower located in the center of the Rocca, adorned with the civic clock. The terrace overlooking the square was erected in 1675, in conjunction with the opening of the monumental arch of access to the city center.