The fortified complex called 'Citadel' is located on a natural protected hill, located where the main commercial roads intersect in Mezdra. The area of the Iskar River is inhabited since the end of the Stone Age and the beginning of the Copper Age, respectively the second half of the 5th century BC. After these prehistoric populations, who lived in the first known historical period of the area, the ancient Thracians were established here. In the I century the place was conquered by the Roman Empire, and in the seventh century, with the great migration of the peoples of Asia, came here the Slavs, and later the Bulgarians of Asparuh. In the eleventh century, the Byzantine emperor Vasile the Great conquered the northwestern Bulgarian lands. The area was then included in the Ottoman Empire for several centuries.
In 2013, the entire complex is restored and tourist routes are built. You can see the remains of the fortified settlements of different times, the “Sanctuary of the Tour”, a pagan worship center from the 3rd century. In a permanent exhibition hall are exhibited objects and archaeological discoveries from the 5 historical periods and a model of the Roman fortress “Kaleto”, dating from the 2nd-5th century. In a separate building are the handicraft workshops, the information center and the souvenir shop.
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.