Lüdinghausen, Germany
1120
Mechernich, Germany
13th century
Mechernich, Germany
15th century
Hörstel, Germany
c. 1400
Morenhoven, Germany
12th century
Euskirchen, Germany
12th century
Heistern, Germany
1333
Lüdenscheid, Germany
14th century
Warburg, Germany
c. 1250
Bad Münstereifel, Germany
13th century
Salzkotten, Germany
1347-1357
Petershagen, Germany
1306
Bonn, Germany
14th century
Nörvenich, Germany
1400
Euskirchen, Germany
13th century
Harth, Germany
14th century
Schleiden, Germany
c.1300
Euskirchen, Germany
14th century
Euskirchen, Germany
14th century
Schleiden, Germany
12th 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.