M4 (Istanbul Metro) 2.02

Line M4, officially referred to as the M4 Kadıköy–Tavşantepe line, is a 26.5km, 19-station rapid transit line of the Istanbul Metro. Running between Kadıköy and Tavsantepe, it is currently the only rapid transit line operating on the Asian side of Istanbul. The M4 mostly runs under State road D100, parallel to the Istanbul-Ankara Main Line and is entirely underground.The M4 opened on 17 August 2012 with a large ceremony in Kadıköy, in which Prime Minister Recep Tayyip Erdoğan personally took part in. On 29 October 2013, with the opening of Marmaray rail service under the Bosphorus, Ayrılık Çeşmesi station was opened to allow passengers to transfer between lines.On 10 October 2016, 3 new station added to the line .HistoryA plan to build a subway line on the Asian side of İstanbul was approved in 2005. In 2008, a 751 million construction contract was awarded to a consortium of Astaldi, Makyol and Gülermak. The rolling stock was ordered from the Spanish company CAF. In mid-2010, the construction of the tunnels was completed and the track laying started. The route has connections with TCDD's Marmaray system at Ayrılıkçeşmesi and the İstanbul Metrobus system at Ünalan. Scheduled opening date was December 2011 up to Kartal, however it was postponed due to signalization works.