Grimbergen Abbey is a Premonstratensian monastery established in 1128 in the place of an earlier foundation of Augustinian Canons.
The abbey itself was dissolved in 1796 in the aftermath of the French Revolution, but the abbey church of Saint Servatius survived as the parish church of Grimbergen. After the French Revolution the abbey was reinstated. The building in its present form dates from 1660 and is considered one of the most beautiful and best-integrated Baroque churches in the Low Countries. It was elevated to the status of basilica minor in 1999.
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.