The Bosphorus Strait is a strait that separates Turkey from parts of Europe and parts of Asia, this strait connects the Sea of Marmara with the Black Sea. The Bosphorus Strait has a length of 30 km, with a maximum width of 3,700 meters in the north, and a minimum of 750 meters between Anadoluhisarı and Rumelihisarı. Its depth varies between 36 to 124 meters.
The edge of the strait is densely populated, one of the cities being Istanbul.
There are three bridges that cross the Bosphorus Strait, the first is the Bosphorus Bridge which has a length of 1,074 meters and was completed in 1973. The second, the Sultan Mehmet Fatih Bridge with a length of 1,090 meters and was completed in 1988 about 5 km north of the first bridge, and the latest is the bridge Sultan Selim which was completed in 2016.
Marmaray is a train tunnel, which has a length of about 1,400 meters, this tunnel is under the strait, with a depth of about 55 meters.