Castillo de Doña Blanca is a tower built in the 15th or 16th century to watch the Cádiz bay. It is named after lady Blanca de Borbón, who was imprisoned there.
The tower is built to the archaeological area. The remains of walls, necrópolis and parts of houses date from the eighth to the third century BC and were built by the Phoenicians. It is considered an ancient city with a significant development and urban planning, which shows the great power of this port city. The first traces of occupation in the mountains and around date back to the Copper Age.
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.