Although the origins of Alcázar de Toro castle date back to the 10th century, its current construction dates from the 15th century. Witness of important historical events, the Alcazar de Toro is one of the main buildings of the city.
After the división of León and Castile in the mid-12th century, Toro remained in the kingdom of León. In 1199 Alfonso 9th married Doña Berenguela and between 1188 and 1195 he started the construction of the castle and the walls. Sancho IV donated Toro its fortress to his wife, María de Molina, in 1283, and she rebuilt the old castle giving it the present structure. In the mid-19th century the castle was in ruins, having been used mostly to store gunpowder.
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.