GWR '31xx' 2-6-2T locomotive asisting a '28xx' 2-8-0 goods engine up the 1 in 100 gradient from the eastern end of the Severn Tunnel, the longest in Britain at four miles and 628 yards, c 1930. The tunnel, opened by the Great Western Railway (GWR) in 1886 provided a direct line to South Wales instead of the previous route via Gloucester. The tunnel reaches the lowest point on a British railway, 144ft below sea level. Photograph by Godfrey Soole.
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