An old fortification of the Frankopans, built during the wars against the Turks, Slovin was first mentioned in the 12th century. The old fort was property of the Frankopan family since the 15th century, joined by an old Franciscan monastery from the same period. Later, this town has been called Slunj. In the 16th century the town was ravaged by the Ottoman wars and turned into a military outpost of the Croatian Military Frontier, but by the end of the 17th century the settlement was rebuilt into the Slunj as it exists today. The castle has been developed to a fortress and served as headquarters for the commanding general of this area.
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.