This is the story of the Byzantine monuments of Istanbul, the city known in the medieval period as Constantinople and in classical antiquity as Byzantium. Constantinople was the capital of the Byzantine Empire from 330 until 1453 and was renowned for the beauty and grandeur of its churches and palaces. The extant Byzantine monuments of Istanbul include more than twenty churches, most notably Hagia Sophia, as well as the remains of the land and sea walls, the Hippodrome, imperial palaces, commemorative columns, reservoirs and cisterns, an aqueduct, a triumphal archway, and a fortified port. They are described here in chronological order and in the context of their times, through the political, religious, social, economic, intellectual, and artistic developments in the dynasties that came to power during the turbulent Byzantine Age. A major part of the architectural and artistic heritage of Byzantium, these monuments also serve as a link between the world of classical antiquity and the new epochs of early modern Europe and the Ottoman Empire.