Among the remains of the Solin buildings, of particular interest is the complex known as Gradina (Hill-Fort), next to the very river and the Roman town’s eastern walls. A church of an unusual ground plan, built over the Roman époque remains, is today situated within a medieval fortress. This was built, according to some authors, by the Split archbishop Ugolino de Mala Branca (1349-1388) to protect the people of Split from the people of Klis. Today, it is in a fortress built during the Venetian-Turkish wars, in the 16th century.
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.