Constantinople

In 324, the ancient city of Byzantium was made the new capital of the Roman Empire by Emperor Constantine the Great, after whom it was renamed, and dedicated on 11 May 330. From the mid-5th century to the early 13th century, Constantinople was the largest and wealthiest city in Europe. The city became famous for its architectural masterpieces, such as Hagia Sophia, the cathedral of the Eastern Orthodox Church, which served as the seat of the Ecumenical Patriarchate, the sacred Imperial Palace where the Emperors lived, the Galata Tower, the Hippodrome, the Golden Gate of the Land Walls, and opulent aristocratic palaces. The University of Constantinople was founded in the fifth century and contained artistic and literary treasures before it was sacked in 1204 and 1453, including its vast Imperial Library which contained the remnants of the Library of Alexandria and had 100,000 volumes. The city was the home of the Ecumenical Patriarch of Constantinople and guardian of Christendom's holiest relics such as the Crown of thorns and the True Cross.

Constantinople was famed for its massive and complex defences. The Theodosian Walls consisted of a double wall lying about 2 kilometres to the west of the first wall and a moat with palisades in front. This formidable complex of defences was one of the most sophisticated of Antiquity. The city was built intentionally to rival Rome, and it was claimed that several elevations within its walls matched the 'seven hills' of Rome. Because it was located between the Golden Horn and the Sea of Marmara the land area that needed defensive walls was reduced, and this helped it to present an impregnable fortress enclosing magnificent palaces, domes, and towers, the result of the prosperity it achieved from being the gateway between two continents and two seas . Although besieged on numerous occasions by various armies, the defences of Constantinople proved impregnable for nearly nine hundred years.

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