Sometimes described as 'the crossroads of Europe and Asia',
Istanbul - formerly Constantinople - is a vast, heaving
metropolis with an imperial history that stretches back for more than 1,500
years. No longer Turkey's capital but still the cultural heart of the nation,
this city of 13 million sprawls across both sides of a land bridge spanning two
Istanbul's unique position on the Bosphorus Strait, which connects the Black Sea to the Sea of Marmara and the Mediterranean, has resulted in the city being a jealously guarded centre of world trade since the Byzantine era.