Llantrisant and Taff Vale Junction Railway
In time the Canal became overwhelmed by the volume of traffic, and encouraged by the successful opening of railways with more advanced technology than the horse tramways of previous years, the Taff Vale Railway was promoted. It was authorised by Parliament in 1836 and it opened between Merthyr and Cardiff docks in 1841. The line passed close to the Maesmawr workings but did not make a connection.
Glamorgan
The first railway network to be built in Glamorgan, the Taff Vale Railway, was also the first in Wales. Linking the ironworks of Merthyr to the ports of Cardiff, the Taff Vale line was given royal assent in 1836, with work commencing the same year. It was completed in 1840, and as well as carrying goods the trains made limited passenger trips from the very beginning. By 1856 the Taff Vale Railway was extended to service the top of the Rhondda Valleys at Treherbert and Maerdy, which allowed the exploitation of the minefields in one of the most coal-rich areas of Britain. The second major railway to open was the South Wales Railway, linking Gloucester in England to Neyland. The line was designed to link the coalfields of Glamorgan to London, and was also part of Isambard Kingdom Brunel's vision of a transport link from London to New York. The South Wales Railway serviced Cardiff, Bridgend, Neath and Swansea, with its final destination within Glamorgan being Loughor, before continuing through Carmarthenshire. Other railway lines that opened during the mid to late 19th century included the Vale of Neath Railway, the Swansea Vale Railway and the Rhymney Railway; all designed with the primary purpose of transporting metals and coal from the uplands of the county to the ever-expanding ports. The cargo carried on these lines was of a very high volume, and in 1850 the Taff Vale Railway was transporting 600,000 tons of coal per annum.