The Rhondda Line is a railway line in South Wales from Cardiff to Treherbert. The line follows the Merthyr Line as far as Pontypridd, where it then diverges to continue along the Rhondda Valley.
The line is currently operated by Arriva Trains Wales (ATW) as part of the Valley Lines network. ATW replaced the previous franchise, Wales & Borders Trains in December 2003.
The first section of the line, as far as Pontypridd, is historically, part of the Taff Vale Railway, from Cardiff to Merthyr Tydfil. At Pontypridd the Rhondda branch diverges and follows the course of the Rhondda Valley. Now single track beyond Porth, the branch suffered from being singled in the early 1980's, just prior to the commencement of the revival of the Valley Lines network. By 1986 a passing loop was constructed at Ystrad Rhondda station (itself newly built, with the original station of that name renamed Ton Pentre), to enable a half hourly service to be introduced. Another new station was opened at Ynyswen on the same day.
Rhondda Line - Principal stations