Boulogne-sur-Mer, France
13th century
Villers-Châtel, France
14th century
Condette, France
13th century
Roost-Warendin, France
1743
Esquelbecq, France
1606
Fresnicourt-le-Dolmen, France
15th century
Potelle, France
1290
Bours, France
12th century
Saint-Waast, France
18th century
Esnes, France
1007
Audignies, France
15th century
Barly, France
1782-1784
Tramecourt, France
1615
Estrée-Blanche, France
1443
Cambrai, France
1850
Grand-Rullecourt, France
1746
Grand-Rullecourt, France
1746
Trélon, France
12th century
Liettres, France
1470s
Couin, France
1745-1749
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.