Welcome to the Marmaray Web-site. On this site you will be able to find information about one of the most challenging infrastructure projects in Turkey, in fact one of the most interesting projects in the world - the Marmaray Rail Tube Tunnel and Commuter Rail Mass Transit System in Istanbul.

The site will be updated regularly as the Project progresses. On the grey top bar you will be able to link to the main topics. At the top left of each page you will find under each main topic a number of related sub-topics, and at the bottom left you will be able to find some interesting articles regarding "what is hot right now".

DLH hope that you will enjoy your "first journey" searching the web-site for information about.

The Marmaray Project

Marmaray Project

The Marmaray Project is the upgrading of approximately 76 kilometers of commuter rail from Halkalı to Gebze. The red alignment on the map shows the parts of the railway that are above ground and the white alignment shows the new railway system that will be constructed in tunnels under the Istanbul Strait.


Istanbul is a city where historical and cultural values must be preserved and at the same time modern railway facilities have to be installed to decrease the environmental impact of public transportation and increase the capacity, reliability and comfort of the railway systems

The Project provides an upgrading of the commuter rail system in Istanbul, connecting Halkalı on the European side with Gebze on the Asian side with an uninterrupted, modern, high-capacity commuter rail system.

Railway tracks in both sides of Istanbul Strait will be connected to each other through a railway tunnel connection under the Istanbul Strait. The line goes underground at Yedikule, continues through the Yenikapı and Sirkeci new underground stations, passes under the Istanbul Strait, connects to the Üsküdar new underground station and emerges at Sögütlüçesme.

This Project is one of the major transportation infrastructure projects in the world at present. The entire upgraded and new railway system will be approximately 76 km long. The main structures and systems; include the immersed tube tunnel, bored tunnels, cut-and-cover tunnels, at - grade structures, three new underground stations, 37 surface stations (renovation and upgrading), operations control centre, yards, workshops, maintenance facilities, upgrading of existing tracks including a new third track on ground, completely new electrical and mechanical systems and procurement of modern railway vehicles.