Espalion, France
11th century
Loubens-Lauragais, France
15th century
Alrance, France
15th century
Altier, France
1498
Coupiac, France
15th century
Saint-Étienne-Vallée-Française, France
14th century
Pourcharesses, France
1578
Onet-le-Château, France
1518-1519
Fenouillet, France
11th century
Aujac, France
12th century
Salvagnac-Cajarc, France
13th century
Lacaze, France
15th century
Coustaussa, France
12th century
Allègre-les-Fumades, France
12th century
Saint-Béat, France
12th century
Sainte-Mère, France
13th century
Termes-d'Armagnac, France
13th century
Livers-Cazelles, France
13th century
Rouze, France
11th century
Padern, France
11th century
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.