The Torre Matilde is the oldest building in Viareggio and a symbol of the city. So called because it was wrongly attributed to Duchess Matilde of Canossa, this 16th-century building was the centre of the city's mercantile and shipping life for centuries. In the mid-1400s the canal-harbour of Burlamacca was the only outlet to the sea for the state of Lucca, which benefitted increasingly from Florentine traffic merchants and from the emergence of a lively maritime town. The later retreat of the sea meant that the port needed the construction of a new defensive tower: the Torre Matilde.
Built between 1534 and 1542, it could house a garrison of around fifteen soldiers. Rounded compartments, varying in size between 7.7 and 8.9 square metres, were spread over three floors; there was a cistern underground and a covered terrace.
In the 18th century the Torre Matilde was deprived of its defensive role by an advancing coastline, and replaced in 1788 by a new fortification at the mouth of the canal. At the same time, however, the Torre was involved in a freakish incident, when during a terrible storm a bolt of lightning struck the building next to its gunpower store, which miraculously failed to explode. The people of Viareggio voted to commemorate this mercy forevermore, inaugurating the festival of the 'Voto del Comune', which takes place every year on April 15.
After that the tower was assigned the role of looking out for enemy ships, fires, or for summoning the citizens to take up arms. From the beginning of the 19th century it was used as a prison, and after 1810 it was used for telecommunications. After the war it was abandoned and remained unused until 1970, when restoration work began. Now it is open to the public, a cultural monument used mainly to host exhibitions of figurative art.