Turkey’s Marmaray Project: a 153-year-old dream becomes reality
11 April 2014 • Author(s): Süleyman Karaman, Director General and Chairman of the Board, Turkish State Railways (TCDD)
On 29 October 2013, an inauguration ceremony took place in Turkey to mark the opening of a rail tunnel beneath the Bosphorus, connecting the European and Asian sides of Istanbul. Part of the wider Marmaray Project, this rail connection is built 60m below sea level and is the world’s deepest immersed tube tunnel and constructed to withstand earthquakes.
As well as the undersea rail tunnel under the Bosphorus, the Marmaray Project consists of the modernisation of existing commuter lines between Halkalı-Yedikule on the European side and Söğütlüçekşme-Gebze on the Asian side, plus the procurement of new rolling stock to be operated along the route.
The rail tunnel underneath the Bosphorus is 13.6km-long and runs between Üsküdar on the Asian side and Sirkeci on the European side. Part of the crossing includes a 1.4km section of immersed earthquake-proof tube tunnel.
Services have initially opened for operation between Kazilicesme and Üsküdar. Once the rest of the project is completed, the line will ultimately run for 76.3km from Halkalı in the west to Gebze in the east, reducing the journey time from 1 hour and 45 minutes (by train and ferry) to 1 hour and 4 minutes. With a capacity of 75,000 passengers, one way per hour, the line is expected to carry one million passengers per day.