Castillo de Salobreña dates from the 10th century. The current structure which was built during the Nasrid dynasty. Trapezoidal in shape, it has four towers. It has 3 enclosures: the disposition of the interior comes from the old Nasrid palace; the other two, with a defensive function, are a Castilian extension of the end of the 15th century. Refreshing internal gardens surround the architectonic volumes. From its towers it is possible to see the urban network of Salobreña, the fertile plain, the Mediterranean Sea, the close mountain ranges and, even, Sierra Nevada.
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.