The Bosphorus connects the Black Sea with the Aegean and Mediterranean seas and has been used as a major trade and transportation artery for thousands of years. It is also considered to be a border between Europe and Asia. Because of the strategic importance of the Bosphorus, the city of Istanbul has often traded hands and has had many names over recorded history including Constantinople, New Rome and Byzantium. Beginning in 1453, the city was the seat of the Ottoman Empire and is now the largest city in the Turkish Republic and the home of over 14 million people, making it more populous than either the cities of New York or Los Angeles.

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