Walls of Lastra a Signa, Medieval defensive wall in Lastra a Signa, Italy.

The Walls of Lastra a Signa form an irregular trapezoidal defensive structure with three gates and eight square towers built into the stone fortification. The system surrounds the old town center with varying wall heights and defensive features adapted to the local terrain.

A fortified village existed here before the 11th century, held by the Cadolingi of Fucecchio and then by the Gangalandi until the 13th century. Florence took it in the 14th century, certainly before 1365, when Pisa besieged it. In 1377 the circuit was rebuilt with battlements and many towers, finished between 1400 and 1403, making it one of Florence's strongest outposts against Pisa. In 1529 it resisted imperial troops bound for the siege of Florence but was taken and sacked.

The gates keep their medieval names: Porta Pisana faces the road to Pisa, Porta Fiorentina faced Florence, and the Portone di Baccio carries a family name. The north-eastern stretch is the best preserved, though houses built against its inner face hide much of it. Restoration work on the western section began in 2020.

The south-western side is almost entirely gone, so the circuit is not continuous; the best-preserved stretches are the north-eastern side, with four towers, and the north-western side, with three towers and the Porta Pisana. The Portone di Baccio, on the south-western side, lost its inner face in Allied bombings. The western part of the walls was under restoration during 2020.

The southeastern section displays irregular stonework and traces of repairs from different periods, revealing how the fortification was modified over time. These varying construction techniques in one wall tell the story of multiple reinforcements and adaptations across centuries.