The Château de Beaucaire is a ruined castle in the commune of Beaucaire. Existing structures date from the 12th and 16th centuries, with other elements from various times in the Middle Ages.
First built in the 11th century, the castle was torn down on Richelieu's orders. It used to be protected by a wall, the trace of which can still be followed. It includes a strange polygonal tower perched on a rocky spur, the façades dominating the sheer drop, and a fine round corner tower. Once inside the walls, a staircase leads to a small Romanesque chapel with a charming, sculpted tympanum, and then to the musée Auguste Jacquet. The museum has exhibits on the region's archaeology (dating back more than 40,000 years) and popular arts and traditions.
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.