Ligny Tower is a coastal watchtower built between 1671 and 1672 at a strategic position on the city's western coast. Today, the tower is in good condition, and it is open to the public as an archaeological museum.
Ligny Tower was built on a narrow strip of land on Trapani's western coast, to defend the city from attacks by the Barbary corsairs. It was named after the Viceroy of Sicily, Claude Lamoral, 3rd Prince of Ligne, who had ordered its construction. The tower was designed by the Flemish architect Carlos de Grunenbergh. It has a square base with scarped walls, with four corner turrets which originally contained lanterns.
A passage connecting the tower with the mainland was built in 1806, and guns were installed on the tower's roof until 1862. It was subsequently used as a semaphore station, but it was eventually abandoned.
In World War II, the tower was used by the Regia Marina and was armed with anti-aircraft guns.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.