Clairmarais owes its origin to the famous Cistercian abbey founded by St. Bernard in 1140. He gave the village the name of Claromarisco (later to be Clarus Mariscus and then Clermarez) because of the huge marshes and many rivers in the vicinity. The Dutch Klaarmares and West Flemish Cleremeersch names reflect the nature of the terrain, too. Clairmarais became a fully-fledged common in 1790 when the abbey was going to be destroyed and sold as a national asset during the French Revolution.
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.