The Moorish fortress or Alcazar of Carmona rises above the Puerta de Sevilla (Gate of Seville), forming an almost impregnable defensive complex. It underwent major alterations in the 14th and 15th centuries. Theestoration work carried out between 1973 and 1975 included the refurbishing of several sections as venues for staging cultural events.
Puerta de Sevilla origin dates back to the 9th century BC. The Carthaginians created the first layout, of heavy rectangular appearance, and made it their bastion against the Romans. The Romans reinforced and restored the structure with a set of gates which is still preserved. Many interventions were carried out from the 12th century onwards.
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.