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https://images.mapsofworld.com/answers/2017/06/What-are-the-oldest-Subway-systems-in-the-World.jpg800509The London Underground, commonly referred to as ‘The Tube’, is the oldest underground subway system in the entire world. The oldest underground railway system, the Metropolitan Railway was completed in 1863, and later incorporated into the London Underground as part of the Circle, Hammersmith & City and Metropolitan Lines. TheRead More...739 total views, no views today