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.
South Wales Railway
The Taff Vale Railway had been opened between Cardiff and Merthyr in 1840 and 1841, and the company went on to expand its network considerably. It extended south from its Cardiff terminus to the Bute West Dock in Cardiff in 1848, so that the South Wales Railway needed to cross it.