Osman Gazi Bridge

Osman Gazi Bridge (OGK) is the suspension bridge between Dilovasi Dil Cape of Izmit Bay and Altinova’s Cape of Herzegovina in the east of the Marmara Sea within the scope of Gebze – Izmir Highway Project.
The middle span of the suspension bridge built within the scope of Gebze-Orhangazi-Izmir Highway Project is 1,550 meters and the total length is 2,682 meters.
The tender announcement of the Gebze – Izmir motorway project, published at the beginning of 2008, included a plan for three-way, three-way strip (six-lane) road and one round trip and two railway lines on the Izmit Gulf bridge. However, in August 2008, the railway lines were removed with the “No. 1 zeyilname” and on September 27, 2010, the non-railway Gulf bridge and the Gebze – Izmir highway contract were signed.
The gebze-Orhangazi-Izmir Highway, which has a project cost of 10 billion TL, has a total length of 433 kilometers, including 384 kilometers of highway and 49 kilometers of connection road, including Izmit Gulf Crossing, which is a 10 billion TL project made by Nurol, Özaltın, Makyol, Astaldi, Yüksel, Göçay joint venture.
The 2,682-meter-long Izmit Gulf Crossing Bridge, which constitutes the largest leg of the Gebze-Orhangazi-Izmir Highway Project, which will reduce the 8–10 hour transportation between Istanbul and Izmir to 3.5 hours and the 2.5-3 hour transportation between Istanbul and Bursa to 1 hour, became the 4th bridge with the largest medium span in the world with a medium span of 1,550 meters.
The cost of the bridge was $1.2 billion and the total cost along with the highways was $6.5 billion. The initial price of $31 for the bridge, which is guaranteed to pass 40,000 vehicles a day, rises every year as much as inflation in the United States. Osmangazi Bridge will have a guaranteed revenue of $7.8 billion during the 15 years and 7 months of operation. In 2019, 8,486,000 vehicles crossed the bridge, which will be operated until 2035. The number of vehicles that did not pass was 5,754,000. The cost to the Treasury reached 2 billion 35 million TL for 2019.