Crossings
The waters of the strait are traversed by numerous ferries. Two suspension bridges cross the Bosphorus. The first of these, the Bosphorus Bridge, is 1,074 m (3,524 ft) long and was completed in 1973. The second, named Fatih Sultan Mehmet (Bosphorus II) Bridge, is 1,090 m (3,576 ft) long, and was completed in 1988 about 5 km (3 mi) north of the first bridge. The Bosphorus Bridge forms part of the O1 Motorway, while the Fatih Sultan Mehmet Bridge forms part of the Trans-European Motorway.
Plans for a third suspension bridge, which will allow transit traffic to by-pass the city traffic, have been approved by the Ministry of Transportation in 2012. The construction of the project was awarded to the İçtaş-Astaldi consortium on May 29, 2012. The bridge will be built near the northern end of the Bosphorus, between the villages of Garipçe on the European side and Poyrazköy on the Asian side. It will be part of the "Northern Marmara Motorway", which will be further integrated with the existing Black Sea Coastal Highway.
Another crossing, the Marmaray tunnel, is a 13.7 km (8.5 mi) long undersea railway tunnel currently under construction and is expected to be completed in 2015. Approximately 1,400 m (4,593 ft) of the tunnel will run under the strait, at a depth of about 55 m (180 ft).
An under sea water supply tunnel with a length of 5,551 m (18,212 ft), named the Bosphorus Water Tunnel, was constructed in 2012 to transfer water from the Melen Creek in Düzce Province (to the east of the Bosphorus strait, in northwestern Anatolia) to the European side of Istanbul, from a distance of 185 km (115 mi).
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