Trani has lost its old city walls and bastions, but the 13th-century fort has been extensively restored as a museum and performance venue and is open to the public.
The castle was commissioned by Frederick II of Swabia in 1230. It was completed three years later, although consolidation of the structure continued for a further fifteen years. Like many other castles, it was modified in the 16th century when Charles V reinforced the defensive structure by adding two bastions equipped with fire arms.
The Castle, with its quadrangular base, is one of the finest existing examples of Swabian defensive architecture. Originally featuring square-base towers on each corner and a central courtyard, it was later fortified with the addition of an external wall. It stands by the sea and was, in the past, directly linked to the water. It used to have a wooden drawbridge.
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.