The dread of a new disaster, a disaster that everyone who lives in Istanbul knows will come from the Bosphorus: I think about it most while in bed. In the early hours of the morning, a ship's horn will interrupt my sleep. If I hear a second blast - long and deep, so powerful that it echoes in the surrounding hills - I know there's fog on the straits. At regular intervals on foggy nights, I'll hear the gloomy horn from the Ahirkapi Lighthouse, where the Bosphorus opens out into the Marmara. And as I swim in and out of sleep, an image will form in my mind of a huge ship struggling to find its way through treacherous currents.

In what country is this ship registered, how big is it, and what is its cargo? How many people are on the bridge with the pilot, and why are they so concerned? Are they caught in a current, or have they noticed a dark silhouette coming at them out of the fog? Have they strayed from the shipping lane, and if so are they sounding the horn to warn any ships that might be near? When Istanbullus hear ships' horns as they're tossing and turning in their sleep, the pity they feel for the men on the ship merges with their dread of disaster to create a fearsome dream about everything that could ever go wrong on the Bosphorus . . . for those who wake up in the night in Istanbul, most get back to sleep by counting the hornblasts. And perhaps in their dreams, they imagine themselves on a ship moving through the fog to the brink of disaster.

- from Istanbul, Memories & the City, Orhan Pamuk