Marmaray is a three-part suburban line improvement project that will unite the European and Asian sides under the Bosphorus. Marmaray is a Eurotunnel railway project in the English Channel. Halkalı and Gebze. However, they have connections to the Istanbul metro. 1 will reduce the transportation time of millions of people and save energy and time. Bosphorus Bridge and FSM Bridge will reduce the workload.
When the construction is completed, the line connected to Marmaray, 1,4 km. (Tube tunnel) and 12,2 km. (Drilling tunnel) TBM Bosphorus crossing and European side Halkalı- It is planned to be approximately 76 km in length between Gebze and Haydarpaşa on the Anatolian side. Railways of different continents will be combined with tube tunnels immersed under the Bosphorus. The Marmaray Project with the 60,46 meter has the world's deepest immersion tunnel used by rail systems. The lifetime of the project is 100 years.