Marmaray

At a glance

Dates: From 2013.

What came beforeAI-assisted

Istanbul's European and Asian sides were connected only by ferries and bridges, with no direct rail link across the Bosporus. Two separate commuter rail lines existed: the Halkalı–Kazlıçeşme line on the European side and the Gebze–Haydarpaşa line on the Asian side, but they terminated at the strait's shores.

Catalyst / how it startedAI-assisted

Turkish authorities recognized the need for integrated public transportation across the Bosporus to reduce congestion and improve connectivity between Europe and Asia. A tunnel beneath the Bosporus was proposed as the solution to link the two existing rail lines into one continuous network.

Who was involvedAI-assisted

The Turkish government, through the Ministry of Transport and the Istanbul Metropolitan Municipality, led the project. Japanese firms, including Nippon Sharyo and Kawasaki Heavy Industries, supplied trains and technology for the system.

TimelineAI-assisted

Construction began in 2004 with the underwater tunnel boring. The tunnel was completed in 2011, followed by track installation and system integration through 2013.

Marmaray officially opened on October 29, 2013, with the first passenger service connecting Halkalı to Gebze via the 13.6-kilometre undersea tunnel.

What happened

History Construction started in 2004 and was originally intended to be completed by April 2009. [ 1 ] After multiple delays caused – among other things – by the discovery of historical and archaeological sites along the route as new stations were built, the first phase of the project was finally opened by president Erdoğan on 29 October 2013. [ 2 ] [ 3 ] The second phase of the project was scheduled to open in 2015 but work once again stopped in 2014. [ 4 ] [ 5 ]

Marmaray or B1 Commuter Train is a 76.6-kilometre-long (47.6 mi) commuter rail line located in Istanbul, Turkey. The line runs from Halkalı, on the European side, to Gebze, on the Asian side, along the north shore of the Sea of Marmara. Mostly using the right-of-way of two existing commuter rail lines, the Marmaray line linked the two lines via a tunnel under the Bosporus strait, becoming the first standard gauge rail connection between Europe and Asia.