Monzón de Campos Castle was built in the 14th century by the Rojas family on the remains of an earlier castle which was contemporary one. The keep, made of high quality ashlar masonry, has no openings besides a couple of small arrow slits which gives it a severe appearance.
The oldest part is the elevated entrance of the present tower of homage.The coat of arms on the pointed arch of the main gate belongs to the Rojas family.
Inside, the castle has not preserved the original distribution except in the tower. A Romanesque door was added to the tower of homage. It was brought in from a church that had been covered by the water of the dam in Aguilar de Campoo. The village of Monzón, with its castle, was the centre of a county donated to the Ansúrez family by the kings of León during the 10th and 11th centuries and in the 15th and 16th centuries it was owned by the Rojas, a family from Burgos that since 1530 had the title of Marquises of Poza. They are likely to have built the present castle in Monzón de Campos.
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.