Torre della Castagna, Medieval tower on Piazza San Martino, Florence, Italy

The Torre della Castagna is a medieval tower standing near the House of Dante, built with sturdy stone walls and narrow windows characteristic of defensive architecture. The structure rises several stories and retains its original defensive features to this day.

The tower was already built in 1038, when Emperor Conrad II donated it to the monks of the adjacent Badia Fiorentina to defend the monastery. From 1282 it housed the meetings of Florence's priors until the Palazzo dei Priori (now Palazzo Vecchio) was built. It was spared the truncation of towers in the second half of the 13th century because of its neutral origin.

The tower takes its name from a voting method where the city's guild leaders used chestnuts placed in bags to count votes during important civic matters.

The tower is located near the Dante monument in central Florence and is easy to reach on foot. The surrounding area is well-maintained and the location offers good sightlines for viewing the structure and its architectural details.

The tower's name comes from the chestnuts (castagne) the priors placed in bags when voting. Florentines call boiled chestnuts ballotte, and etymological dictionaries trace the word ballottaggio (runoff vote) to ballotta, the ballot used in old assemblies. The tower was spared the truncation that lowered other Florentine towers in the second half of the 13th century because of its neutral origin.