Deep underground, below the bustling streets of cities big and small all around the world, subway trains shuttle passengers to their destinations. From the world's oldest subway in London, built in 1847, to the extremely busy Tokyo subway with over 200 stations, subways have been and continue to be a huge part of the daily lives of millions of people. This lively volume explores the engineering marvels of subway systems, which have a history as surprising as the twists and turns of a subway's tracks.