The "Fortezza Vecchia" stands out for its size and the particular reddish color of its bricks on the side of the Medici Port and constitutes, together with the nearby complex of statues "Quattro Mori", the symbol and most characteristic monument of the city of Livorno.
It is an imposing sixteenth-century fortification built to protect the port and the nearby fishing village from which the city of Livorno would later be born.
It was built between 1521 and 1534 by Antonio da Sangallo (designer of numerous other Medici fortresses) on behalf of Cardinal Giulio de' Medici - the future Pope Clement VII - incorporating the already existing fortifications: a Roman tower of which few remains are visible , the beautiful Mastio di Matilde, a massive cylindrical tower built by the marquises of Tuscany in the 9th century and the "Quadratura dei Pisani", a wall built in 1377 by the Maritime Republic of Pisa (which in the Middle Ages used this area as a commercial port until 15th century, when it came under Florentine rule).
The Fortress, initially surrounded by ditches, remained practically an island until a stretch to the north-west was filled in, joining it to the mainland. It has an asymmetric pentagonal shape and is made up of three bastions (instead of the four planned): the one to the south-west called the "Canaviglia" (where a small palace built in 1580 by order of Francesco I dei Medici stands), the one on the opposite side , to the north-east, called the "Capitana", and the intermediate one called "Ampolletta".
During the Napoleonic invasion in 1796, the ramparts in front of the city were raised by French soldiers and equipped with slits for the cannons.
The Fortress was seriously damaged by the bombings of 1943. It is currently in a serious state of decay (a deep crack is visible in the "Capitana" bastion), but important restoration works are underway.