The origins of the Castillo de la Yedra could be Muslims, possibly from the Almohad era. During the 11th and 12th centuries, the first fortress was built, but the current appearance was built by Christians during the 13th and 14th centuries and during the papacy of don Pedro Tenorio. The alcázar was built by the archbishops of Toledo at the end of the 14th century. There is a keep and a small parade ground that surround the alcazar.
Its construction was designed exclusively for military use as a palace of a feudal lord or small court of medieval monarch. That is why its architecture is sober, although compensated by the beauty of the topography of its location and the surrounding landscape.
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.