Quebec City is one of the oldest European settlements in North America. French explorer Jacques Cartier built a fort at the site in 1535, where he stayed for the winter before going back to France in spring 1536. Quebec city was actually founded by Samuel de Champlain, a French explorer and diplomat on 3 July 1608, and at the site of a long abandoned St. Lawrence Iroquoian settlement called Stadacona. Quebec was the capital of New France and, after 1760, of the new British colony.
Quebec is the only North American city to have preserved its ramparts, together with the numerous bastions, gates and defensive works which still surround Old Québec. The Upper Town, built on the cliff, has remained the religious and administrative centre, with its churches, convents and other monuments like the Dauphine Redoubt, the Citadel and Château Frontenac. Together with the Lower Town and its ancient districts, it forms an urban ensemble which is one of the best examples of a fortified colonial city.
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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.