Alignment and Interchanges
The lines are fully underground and has no connection between them. All station names are on the bus lines as well.
M2 Line has interchange between F1 in Taksim and a new interchange tunnel is almost finished between Zincirlikuyu Metrobus station and Gayrettepe station. When the line completed, there will be an interchange at the Yenikapı Marmaray station and İDO Ferry Port; from where it is possible to take the high-speed catamaran Seabus for going to Bursa, Bandırma or Yalova; as well as the other Seabus ports in İstanbul such as Bostancı, Kadıköy, Bakırköy, and Kabataş.
M4 Line has vapur (traditional ferry), motorboat, İDO and nostalgic tram interchange at Kadıköy which is heart of İstanbul's Asian side. When Ayrılıkçeşme Station Complex's construction is finished, Marmaray and M4 will meet here. Also at Ünalan / Uzunçayır, the line has Metrobus interchange just like Gayrettepe in M2.
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