Château de Gourdon was built in the 12th century on the foundations of 9th century fort when the counts of Provence organized their border between the county of Vintimille and Provence. From 1598 to 1905 the castle was the residence of the Marquis de Montauroux. The current castle was built in the 17th century, the first stage in 1610 and the second in 1653.
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.