Castrojeriz village is considered one of the landmarks of historic interest in the Camino de Santiago. Its rich history may take up consideration as castro Visigoth, or perhaps, also, Roman fort, (they say was founded by Julius Caesar) in whose castle was developed important battles between Christians and Moors.
The first mention of this castle dates from the 9th century during the skirmishes with the Muslim forces. There are three clearly differentiated sections: the Roman part which is today reduced to an almost hidden square tower; the Visigoth part comprising the extension to the castle with different masonry work from in the Roman part; and the medieval part.
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.