The years have been gracious to Istanbul. Drawing her age about her like a cloak woven from the strands of 26 centuries, the Turkish city stands astrid the Bosporus in quiet dignity. The swift waters of the Bosporus, a 20-mile strait connecting the Black and Marmara Seas, bisect the ancient city at a point where Europe and Asia touch. Because of its strategic location and protected harbor, called the Golden Horn, Istanbul has been the cornerstone of four civilizations. The first settlement dates to the seventh century B.C. when Byzas, leader of the Megarians, expanded a sleepy village into Byzantium, jewel of the Byzantine Empire, bequeather of a rich architectural heritage to succeeding generations. After the decline of Rome, when its senate ceased to be sovereign of the far-flung Roman world, Emperor Diocletian divided the burden of government among four colleagues. One of them, Constantine the Great, was charged with administering the Eastern provinces. Choosing Byzantium as his capital in 330, he named it after himself—Constantinople. For 1,100 years Constantinople thrived as a great commercial, legal and ecclesiastical center. Then, in the thirteenth century, the city was overrun by Crusaders and not until 250 years later, when Sultan Mehmet II, the "Conqueror," styled it capital of his Ottoman Empire, did the city regain its former glory. Although the "queen of cities" is no longer Turkey's capital (Atatürk called it Istanbul and moved the capital to Ankara in 1922), the city's diverse cultures, acquired through 2,600 years of alternating Eastern and Western influence, combine to lend Istanbul a unique cosmopolitan flavor. As the Turks put it: "If one had but a simple glance to give the world, one should gaze at Istanbul."