The Royal Abbey of Notre-Dame de Lieu-Dieu, founded in 1197 by Richard the Lionheart for Premonstratensian canons, suffered three devastations in 1372, 1484, and 1568. After various trials, it was annexed to a Parisian Premonstratensian college in 1720. The abbey was turned into an agricultural enterprise in 1733 and sold as a national asset in 1791. In 2012, it was acquired and restored by Mr. and Mrs. Alain du Peloux, opening to visitors in 2013.
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.