During the 12th century and onwards, Osthoffen became a fortified castle. Due to a siege lead by the Bishop of Strasbourg in 1410, fire raged through the building, depriving it of its 3rd floor. It was rebuilt as a Rennaissance estate and a private dwelling. More changes were made in the 18th century: courtyard walls were removed and new wide windows enlightened both the façade and the interior. The castle lost its towers during the French Revolution by order of the new authorities, one of the first works undertaken by the new owner was to rebuilt them. Today Château d'Osthoffen is a hotel and event venue.
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.