Château de Noirmoutier is very well preserved and a fine example of 12th century medieval architecture. The first traces of the castle appeared in 830 with the construction of a castrum by the abbot Hilbold, from the monastery of Saint-Philbert. It served to defend the monks and the island's population from the Vikings. The castle was rebuilt in stone in the 12th century by the feudal power who was trying to stabilise the region, notably by preventing Norman pillaging. The island at that time was under the control of the barons of La Garnache. The keep was built by Pierre IV of La Garnache, then an enclosure equipped with towers was built around the lower courtyard. In the 16th century, the castle was held by the La Trémoille family, then viscounts of Thouars.
The castle has resisted numerous attacks, like the English in 1342 and 1360, and again in 1386 under the command of the Earl of Arundelthe Spanish in 1524 and 1588. In 1674 it was taken by the Dutch troops of Admiral Tromp.
Château de Noirmoutier was sold in 1720 to Louis IV Henri de Bourbon-Condé who resold it in 1767 to Louis XV. During the French Revolution, the castle served as a military prison. During the 19th century, the castle was used as a barracks. In 1871, during the Paris Commune, insurgents were imprisoned there. In 1960, a house was built within the castle grounds by the governor of the island and the castle. Today, the keep houses the Noirmoutier Museum.
The keep at the centre of the castle is solid and rectangular. Built of rubble, it has three floors with the lords' residence at the top. The keep has numerous murder holes and defensive turrets at the corners. The rectangular fortification consists of two towers, a single gate and two watch turrets in the four corners. At the beginning of the 18th century, the towers were reconstructed and the keep adapted for artillery.
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.