The Castello di Carlo V was built in 1542 at the behest of the emperor Charles V who commissioned the construction of the architect Gian Giacomo dell'Acaya. The fortress is located in the ancient village of the city of Capua. It has linear geometries and ramparts of a square base and an entrance bridge that rests on arches. Over the centuries the function of the Castle has always remained the defensive function, except during the period of the restoration when it held the role of prison. The castle is not open to the public.
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.