Istanbul Metro
…has the 22nd longest metro system in the world and the 4th longest in Europe as of 2026. The system consists of eleven lines: the lines designated M1A, M1B, M2, M3, M6, M7, M9 and M11 are on the European side of the Bosporus, while lines M4, M5 and M8 are on the Asian side. Due to Istanbul's unique…