The abbey of Vaucelles, old Cistercian abbey founded in 1132 by Saint-Bernard, is the 13th daughter-house of Clairvaux. During the era of prosperity in the 12th and 13th centuries, the community included several hundred monks, lay brothers and novices. The 12th century claustral building is the only remains of this immense abbey, now open to the public. It included the Norman scriptorium, auditorium, chapter room (built in 1170). Vaucelles is the largest Cistercian chapter room in Europe and the acoustics are exceptional. The Sacred Passage where the remains of the first three abbots of Vaucelles, canonized by Pope Alexander III in 1179, are buried.
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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.