Osmangazi Bridge, a landmark road bridge over Turkey's Marmara Sea, cuts travel time dramatically between Istanbul and the country's western provinces. It was opened on June 30, 2016, forming part of a new six-lane Istanbul-Izmir highway. The 421 kilometer highway project is being built through a public-private partnership(PPP) as the first road project in the country to be procured under the build-operate-transfer(BOT) model. The 421km road project will be completed in seven years and involves the construction of a 3km suspension bridge, 30 viaducts (total 18.21km in length), four tunnels (total 7.4km in length) and 209 bridges. It is expected to be finished in 2018.