Two stations have served Porth. The first was opened on 4 February 1861 by the Taff Vale Railway; the line had been open since 10 June1841. On 1 July 1876, the original station was closed, being replaced by a new one approximately to the east. The Rhondda Fawr line to Treherbert was singled north of here in 1981 and most of the 1876 station buildings were replaced in 1984–85. The now defunct Maerdy Branch along the Rhondda Fach valley to Maerdy and the collieries at Mardy and Ferndale used to diverge from the 'main line' to just north of the station at Maerdy Junction. Opened in stages between 1849 and 1856, the passenger service over this route ended in 1964, but mineral traffic to Mardy Colliery continued to run until final closure of the branch in August 1986, when coal from Mardy was then raised from Tower Colliery. The track was subsequently lifted in 1996, but the old formation can still be traced. A passenger service between Porth and was introduced by the Barry Railway on 16 March 1896, running via and., but this ended in 1930 when the service was re-routed via the TVR station at Pontypridd. An unusual ground levelsignal box was installed at the station when the Treherbert line was reduced to single track in 1981, replacing a much more substantial TVR structure. This holds the distinction of the being the last new mechanical box to be built by British Rail, though it had a working life of only 17 years before being abolished in 1998 when the Radyr signalling centre took control of the area.
Services
Monday-Saturday, there is a half-hourly service to via and southbound and to northbound, serving all stations en route except. This drops to hourly in the late evening. There is a two-hourly service in each direction on Sundays, with through trains to. On 20 July 2018, previous franchise operator Arriva Trains Wales announced a trial period of extra Sunday services on the Rhondda Line to Cardiff and Barry Island. This was in response to a survey by Leanne Wood and the success of extra Sunday services on the Merthyr Line and the Rhymney Line.
