Stainz, Austria
1229
Wilhering, Austria
1146
Sankt Georgen am Längsee, Austria
1002-1008
Lilienfeld, Austria
1202
Dorfbeuern, Austria
8th century
Schlierbach, Austria
1355
Bregenz, Austria
611 AD
Schlägl, Austria
1202
Aggsbach Dorf, Austria
1380
Spital am Pyhrn, Austria
1060
Sankt Paul im Lavanttal, Austria
1091
Ybbs an der Donau, Austria
1336
Klein-Mariazell, Austria
1134
Steyr, Austria
c. 1120
Griffen, Austria
1233
Pupping, Austria
1303
Arnoldstein, Austria
c. 1080
Garsten, Austria
1080
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.