Irulegui castle is located on the Sierra de Aranguren in the municipality of Laquidáin.
During the Iron Age it there was a castro de los Vascones. This pre-Roman fort was destroyed around 76 BC. as a consequence of the rebellion.
Although there are legends that suggest the existence of the castle (or, at least, of a defensive structure in this place) during the Almanzor raids in the 11th century, the first reliable documents of the castle dates from the late 12th century.
In 1416 the castle was modernized, adding a triangular structure to the front. In 1494, the kings Catalina and Juan III (Juan de Labrit), agreed its destruction before the push of the Beaumonteses, who controlled the fortress, and consequently, the Pamplona Basin.
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.