Marmaray Tunnel Construction: Marmaray Project, one of the most important projects in the world, is a project that does not pollute the environment by using high capacity electrical energy to maintain Istanbul's urban life in a healthy way, to provide a modern urban life and urban transportation opportunities for the city population.
Istanbul is a city that needs to be protected with historical and cultural values, on the other hand, to reduce the environmental impact of public transportation systems and to establish modern railway facilities to increase the capacity, reliability and comfort of railway systems.
The project is located on the European side Halkalı is based on the construction of the railway subway system and the upgrading of the suburban rail system in Istanbul in order to connect the Gebze districts on the Asian side with a continuous, modern and high capacity suburban rail system.
Railway lines on both sides of the Bosphorus will be connected by a railway tunnel connecting the Bosphorus. The line will go underground in Kazlıçeşme; it will move along the new underground stations Yenikapı and Sirkeci, pass under the Bosphorus and connect to Üsküdar, another new underground station, and re-surfaced at Söğütlüçeşme.