History, numbers and secrets of the third Bosphorus bridge

The record-breaking highlights of the majestic bridge dominating Istanbul

With its 16 million citizens, Istanbul is the 15th largest city in the world by population. But what makes it unique is that it developed over the centuries along the border of Europe and Asia, so it qualifies as the largest city in Europe and one of the top ten Asian cities by size. These rankings may not mean much unless you stop and admire the city from the top of one of the most iconic bridges in the world, the third bridge over the Bosphorus, named after Yavuz Sultan Selim, Sultan of the Ottoman Empire from 1512 to 1520.

All the numbers of a majestic work

Erected by Webuild between 2013 and 2016, the bridge is a hybrid, being both suspended and cable-stayed, and to this day holds various records for its type. Its two towers are 322 meters high (1,056 feet), about ten more than the Tour Eiffel, making the Yavuz Sultan Selim bridge one of the tallest in the world. It is 58,4 meters wide (192 feet), allowing for eight road lanes, two railroad tracks and two pedestrian crossings, befitting one of the largest bridges in the world. By comparison the Golden Gate Bridge is 28 meters wide, barely half as much. And the third bridge over the Bosphorus is 2,164 meters long (7,100 feet), with a central span 1,408 meters long (4,619 feet), making it the longest, suspended, railroad bridge in the world.

For these record numbers, the project employed 176 steel cables to support the beams and it took two years of study and engineering to define the most suitable type of bridge. It is part of the Northern Marmara highway, 260 kms long (160 miles), and was designed to handle 135,000 vehicles a day in order to ease traffic congestion in Istanbul and create a commercial corridor for goods to travel to and from Greece.

After erecting the towers, the span was constructed with 59 ashlars, each 24 meters long and weighing 840 tons, transported by barge along the straight. In total, building the bridge required 241,000 cubic meters of concrete, 125,000 tons of steel for the structure, and the moving of 897,000 cubic meters of dirt.

The transit speed allowed is 120 km/h for road traffic, 160 km/h for passenger trains and 80 km/h for freight trains. One can also walk across the bridge thanks to two gangways running along the external sides of the bridge, each 2,5 meters wide. It’s a safe and breathtaking promenade, given the height, the wind, and the immense expanse of water beneath this marvelous bridge.

The bridge was tested to resist winds of up to 300 kms an hour, though it is shut when the wind reaches 100 km/h because while the bridge holds, vehicles and trains are less stable. Except maybe the Batmobile, which crossed the Yavuz Sultan Selim Bridge for a film.

Looking out towards the Black Sea from the Third Bosphorus Bridge

The bridge dominates the access to the Black Sea, between Garipçe and Sarıyer on the European side and Poyrazköy and Beykoz on the Asian side, underlining the importance of the Bosphorus, which in Greek, boos poros, means ford of the oxen. This narrow bit of sea is 30 kms long, (19 miles), 3,7  (2,3 miles) kms across at its north entrance and just 750 meters across (2,450 feet) between the Ottoman forts of Rumelihisarı and Anadoluhisari. It’s depth ranges from 36.5 meters to 124 meters in the middle of the channel (120 to 408 feet).

Going across the Yavuz Sultan Selim bridge, on the easter side, the horizon expands over the Black Sea, beyond which today is the ongoing war in Ukraine, which one can perceive by the increased traffic of military vessels flowing beneath the span. On the opposite side, the height of the bridge offers a panorama of the area, looking out toward the other bridges, Istanbul and then the Marmara Sea that ships cross before reaching the Aegean and the Mediterranean.

Beyond the Yavuz Sultan Selim bridge, toward Istanbul, the channel is crossed by two more bridges, both suspended. The first has a span of 1,074 meters (3,523 feet), built in 1973 and dedicated to the Martyrs of July 15. The second, the Fatih Sultan Mehmet Bridge, constructed in 1988 by Webuild, is 1,090 meters long (3,576 feet) and is dedicated to the sultan Mohammed the Conqueror. In addition, two tunnels cross the Bosphorus, a railway tunnel opened in 2013 and a road tunnel inaugurated in 2016.