Esslingen Castle has been the city’s most recognizable landmark for almost 700 years. It was built originally in the 13th century and enhanced in 1519-1531. Preserved elements in the Old Town of the corresponding city wall include the Schelztor, the Pliensauturm and the Wolfstor. The castle is open to the public, and the famous Dicke Turm has also recently reopened for visits by guided tours. The ascent of more than 300 steps rewards visitors with a unique view over the city.
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.