The importance of the Boğaziçi (Bosphorus) cannot be overstated. The strait divides the European and Asian sides of İstanbul. It allow passage between the Karadeniz (Black Sea) and the Akdeniz (Mediterranean Sea). Wars, goods, and passengers - like me - have floated up, down and across it for thousands of years. The Boğaziçi connects with the Haliç (Golden Horn), which cuts westward into the European side, and the Marmara Denizi (Maramara Sea) to the south, giving İstanbul its distinct shape and character. Until the metro is expanded to go under the Boğaziçi - this will take quite some time - the enormous "sea buses" remain the most practical way to get from some parts of İstanbul to others. For the average İstanbullu, this might just be a mundane part of the daily commute, but for me, it means a picturesque urban cruise for about $1.