Medieval Town of Dubrovnik is medieval fortress in the area of Višnjica, Ilijaš municipality, Bosnia and Herzegovina. Although there are no precise data on the origin of the city, it is assumed that it was built in the 13th century because it was first mentioned in the Dubrovnik archives, on July 11, 1404.
It is believed that the town was named after the medieval merchants from Dubrovnik who came in that period with the approval of the Bosnian king to exploit the mines of lead, zinc, gold and other precious materials.
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.