Marmaray
commuter rail system operating in Istanbul and Kocaeli, passing under the Istanbul Bosphorus
Marmaray (pronounced [ˈmaɾmaɾaj] ) or B1 (Halkalı – Gebze) 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 (all prior connections ran through Russia and used the incompatible Russian broad gauge). The two existing sections of the line were rebuilt and expanded from two tracks to three tracks, to allow for higher capacity with intercity and freight rail. The name Marmaray is a portmanteau of the words Marmara and Ray, which is Turkish for rail.
History
Construction started in 2004 and was originally intended to be completed by April 2009. 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. The second phase of the project was scheduled to open in 2015 but work once again stopped in 2014. It was restarted in February 2017 and the line finally opened in its entirety on 12 March 2019. The trains came with completely new rolling stock, with carriages that can be walked through from end to end.
This brief starts where responsible research should: with the source description of “Marmaray” as commuter rail system operating in Istanbul and Kocaeli, passing under the Istanbul Bosphorus. Everything that follows is an evidence route, not borrowed authority.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 26, 2026. The linked authority identifier is Q497844. Authority coordinates are 41.019, 28.997. None of the 3 selected statements returned an explicit reference. The first chronological checks are 2004, 2009, 2013 and 2015.
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This entry incorporates text from “Marmaray” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.