The Golden Valley line is the popular name given to the railway line between Swindon and Gloucester and Cheltenham Spa in England. The line was originally built as the Cheltenham and Great Western Union Railway in the 1840s. It was opened between Swindon and Kemble, along with a branch line to Cirencester, in 1841. It was a further four years before the remainder of the line, including the tunnel at Sapperton, was completed.