The strait also experiences significant amounts of international commercial shipping traffic by freighters and tankers. Between its northern limits at Rumeli Feneri and Anadolu Feneri and its southern ones at Ah?rkap? Feneri and Kad?köy ?nciburnu Feneri, there are numerous dangerous points for large-scale maritime traffic that require sharp turns and management of visual obstructions. Famously, the stretch between Kandilli Point and A?iyan requires a 45-degree course alteration in a location where the currents can reach 7 to 8 knots (3.6 to 4.1 m/s). To the south, at Yeniköy, the necessary course alteration is 80 degrees. Compounding these difficult changes in trajectory, the rear and forward sight lines at Kandilli and Yeniköy are also completely blocked prior to and during the course alteration, making it impossible for ships approaching from the opposite direction to see around these bends. The risks posed by geography are further multiplied by the heavy ferry traffic across the strait, linking the European and Asian sides of the city. As such, all the dangers and obstacles characteristic of narrow waterways are present and acute in this critical sea lane.
