Wittichen Abbey is a former Poor Clares abbey founded by Saint Luitgard of Wittichen in 1324. According to Luitgard, who came from the Schenkenzell village of Kaltbrunn-Vortal, God said to her on the site of the monastery: 'Here you are to build me a house!' So she searched for other co-sisters and founded her abbey in the outback of Wittichen with 33 sisters.
The abbey found support from the dukes of Teck and the counts of Geroldseck as well as Queen Agnes of Hungary. Through her intervention the retreat was recognised as an abbey by John XXII. It was in 1540 temporarily closed due to the Reformation and again in the Thirty Years' War (the abbey suffered heavy damages in 1640 and 1663. The monastery was secularized in 1803. After that the monastery came into the possession of the Princely House Furstenberg. Part of the buildings were demolished because of the high costs in the 1850s. The church, the nave and the monastery barn have been preserved, as well as the cemetery.
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.