Torrelobatón Castle is one of the most important and best-preserved fortresses in Valladolid. In the historical epic film El Cid with Charlton Heston the castle played the role of Vivar, hometown of El Cid.
The castle was begun in 1406, when Don Alfonso Enríquez, 1st Admiral of Castile, obtained licence from John II to erect a fortress in Torrelobatón; the only fortification there was a modest stone enclosure surrounding the village. The castle was involved in the Revolt of the Comuneros against Charles I (Holy Roman Emperor Charles V).
It has a square ground-plan, with circular turrets at three of the corners and the keep set into the fourth, protecting the gate. The castle was surrounded by an enceinte, of which there are some remains, and a ditch, now mostly filled in. The entrance to the Torrelobaton Castle courtyard is through a gate with a round-headed arch protected by a portcullis. The keep is the most interesting feature of the fortress. Of considerable height, the upper part is protected by eight turrets supported on accordion brackets, one at each corner and one in the middle of each wall.
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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.