Stockholm, Sweden
17th - 18th century
Stockholm, Sweden
ca. 1270-1300
Uppsala, Sweden
1287-1435
Ekerö, Sweden
1662
Mariefred, Sweden
16th century
Vadstena, Sweden
1346
Gamla Uppsala, Uppsala, Sweden
400-500 AD
Varnhem, Sweden
ca. 1150
Götene, Sweden
12th century
Adelsö, Sweden
ca. 750 AD
Visingsö, Sweden
mid-1100s
Uppsala, Sweden
13th 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.