Schloss Drachenburg is a private villa in palace style constructed in the late 19th century. It was completed in only two years (1882–84) on the Drachenfels hill in Königswinter, a German town on the Rhine near the city of Bonn. Baron Stephan von Sarter (1833–1902), a broker and banker, planned to live there, but never did.
Today the Palace is in the possession of the State Foundation of North Rhine-Westphalia.
References: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.