M5 (Istanbul Metro)

The construction of the 20-kilometre-long (12 mi) line in the west–east direction with 16 stations between Üsküdar and Çekmeköy, and its connection line to the depot with 3 km (1.9 mi) length began on 20 March 2012. Projected to cost about €564 million, the line is built by the Doğuş Construction Group and was expected to open in May 2015; however, the expected opening day was then revised to 20 September 2016, until it became clear that it would not open then. In June 2014, 21 six-car driverless trainsets, manufactured by a consortium of CAF and Mitsubishi, were ordered to operate on the line,^[4][5] the first of which was delivered on 21 November 2016.^[6] According to news in Turkish TV in November 2016, half of the M5 line (Üsküdar - Ümraniye) would open in January 2017, with driverless trains, and then in early 2017 the new opening date was stated to be 22 March providing there are no further delays.^[7] But in April 2017 the opening date had been postponed further to 30 August 2017.^[8] Later it was postponed further, first to 14 September 2017 and then to 29 October 2017.^{[citation needed]} The first stage of the line, running from Üsküdar to Yamanevler, finally opened on 15 December 2017.^[9][10] The second stage, from Yamanevler to Çekmeköy, opened on 21 October 2018.^[11][12] The third stage of the line, and the first phase of the extension to Sultanbeyli, opened on 16 March 2024 from Çekmeköy to Samandıra Merkez (excluding Sancaktepe Şehir Hastanesi station).^[13][14] The fourth and final stage of the line, from Samandıra Merkez to Sultanbeyli, is planned to open on 19 May 2026.^{[citation needed]}

Earlier plans^[15] to extend the line to Sabiha Gökçen International Airport in the future have been cancelled, with the M4 extension now open to this airport.^{[citation needed]}