Why do you think constantinople's location influence its growth and financial success?

Constantinople was on a promontory on the southern entrance of the Bosporus, a strait which separates Europe and Asia and which connects the Mediterranean Sea and the Black Sea (via a small sea in between the two called the Sea of Marmara). This placed Constantinople both on the land route between Europe and Asia and on the naval route between the Mediterranean and the Back Sea, giving her control over these two important routes. An inlet of the Bosporus on the city's northern shore (the Golden Horn) provided a very good harbour. It was this harbour which made the fortune of the city. Two ports were built in this inlet. Hence the strategic position.