The Vale of Neath line, featuring the iconic Crumlin Viaduct, connected South Wales' valleys from the mid-19th century until closure in 1964, marking a significant chapter in Welsh railway history. This book covers the Vale of Neath line, the eastern portion of which was originally the Taff Vale Extension line, opened in the mid 19th Century, and taking in all the locations in this first book. It was unique in South Wales railway history as it was the only line running east to west across several of the valley lines which ran north to south, with connecting junctions into and from each. The line was famous for the iconic Crumlin Viaduct, hailed as one of the best examples of technological achievement during the Industrial Revolution and lasting 107 years until the line was closed as a through route in 1964. The line ran through several important valley towns, creating need for High Level and Low Level stations at several locations. The standard gauge Taff Vale Extension originally ran as far as Mountain Ash where it met and amalgamated with the broad gauge Vale of Neath line from Neath to Aberdare and Merthyr, locations that will be dealt with in future volumes. Fortunately the line was well photographed as the coverage given to each location will show.