Paimpont Abbey was originally built by the King of Dumnonia in the 7th century, probably around 630 AD. It was destroyed by Vikings in the 9th century. The construction of current abbey building was started in 1199. The present buildings are works from the 11th, 13th, 15th and 17th century. Paimpont Abbey was closed down during the Great Revolution in 1790, but several buildings have survived. The Abbey is home to many fine treasures, like a statue of Our Lady of Paimpont, the golden reliquary hand of Saint Judicael and a carved ivory Christ.
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.