From 990 AD, Château de Castelnou served as the administrative and military capital of the Viscount of Vallespir. Its irregular pentagonal plan follows the rocky outcrop on which it was built, this elevated position providing defence against enemy attacks.
The castle was taken by the troops of James II of Majorca en 1286, and again in 1483. Largely demolished in 1559, it was no longer restored or inhabited and deteriorated throughout the 17th and 18th centuries. At the time of the French Revolution it became the property of the commune. It was sold to Viscount Satgé in 1875 and, by 1900, had become again an elegant and habitable fortress. It was acquired in 1946 by Charles-Emmanuel Brousse who was married to Amy Elizabeth Thorpe, a famed American spy. Having been ravaged by a terrible fire, in 1987 it was sold and has since been restored.
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.