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On this day in 1804, the world's first steam-powered train hauled 10 tons of iron and 70 men for nine miles at a speed of five miles an hour in Merthyr Tydvil, South Wales, opening a century whose history would be defined and guided by the expansion of the railway. The engine was designed by Richard Trevithick (1771-1833). Above, a drawing of an earlier Trevithick design, thought to be quite similar to the locomotive that ran in 1804.

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Image: irsociety.co.uk.

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