Stein Castle was built on a rocky promontory above Baden gorge some time before 1000. In the late 11th century the castle came to the Lenzburg family. By the early 12th Century, the cadet line that lived in the castle called themselves the Counts of Baden. In 1172, the castle was inherited by the Kyburg family. When that family died out in 1263, the castle was inherited by the Habsburgs in 1264.
The castle was occupied by a bailiff and was the seat of the Austrian administration for Vorderösterreich (Further Austria) and housed the archive. The castle was besieged and destroyed in 1415 by the Swiss Confederation. It was rebuilt in 1658-70 but was demolished in 1712. It remains in ruins since that time.
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.