The Chapel of Saint Germanus (Chapelle Saint-Germain) is one of the earliest surviving places of Christian worship in the Cotentin Peninsula. It is a small building with walls built from small pieces of shale arranged in a herringbone pattern. The chapel consists of a short nave, and transepts and a choir each formed from an identical apse with half domed roofs. This tri-lobate plan, which is unusual, is the result of a reconstruction in the 9th or 10th century on remains of a palaeo-Christian basilica which has been revealed by archaeological excavations. In the 17th century, the chapel was topped by a tower which in turn replaced an older tower structure.
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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.