The walls of Lucca are a series of stone, brick, and earthwork fortifications surrounding the central city of Lucca in Tuscany, Italy. They are among the best preserved Renaissance fortifications in Europe, and at 4 kilometers and 223 meters in circumference they are the second largest intact example of a fully walled Renaissance city after Nicosia, Cyprus. The current walls of Lucca, which replaced earlier medieval and Roman fortifications, are the result of a construction campaign that started on May 7, 1504, and ended a century and a half later in 1648, with additional structural updates in the second half of the seventeenth century based on new knowledge and construction techniques. These walls play an important role in the cultural identity of the city of Lucca and its surroundings, and as a physical monument to the region's history, and Lucca's longstanding independence as a republic.
The walls were also conceived as a deterrent and have never seen military use. At the time of construction, the Republic of Lucca feared the expansionist aims of the Republic of Florence and subsequently, the Grand Duchy of Tuscany. However, there was never an open war against the Grand Duchy. Although the Republic of Lucca did come into open conflict with the Duchy of Modena in the 16th and 17th centuries, these campaigns occurred exclusively in the Garfagnana, so the city of Lucca never underwent any siege and the walls were never used.