This article needs to be updated. The reason given is: It needs more explanation of the South Wales Metro. Please help update this article to reflect recent events or newly available information.(June 2022)
On 28 March 2020, ownership of the lines between Cardiff and Treherbert, Aberdare, Merthyr Tydfil, Coryton, Rhymney and Cwmbargoed (the "Core Valley Lines") was transferred from Network Rail to Transport for Wales, who leased them to operator AKIL.[6]
On 16 July 2012 the UK Government announced plans to extend the electrification of the network at a cost of £350 million. This was at the same time of the announcement of electrification of the South Wales Main Line from Cardiff to Swansea. This would also see investment in new trains and continued improvements to stations.[7]
The investment will require new trains and should result in reduced journey times and cheaper maintenance of the network. Work was expected to start between 2014 and 2019, but has since been pushed back to between 2019 and 2024.[8]
Lines
The Valley Lines network and surrounding routes
The colours used below are from the official network map (see External links). Stations in bold are major interchanges for the network.[2]
Generally trains run from one line to another, joining at Cardiff Central eliminating the need for changing trains there. However they may not run for the whole length of the line.[9] Services run between:
Bridgend/Barry Island and Merthyr Tydfil/Aberdare - incorporating the Vale of Glamorgan and Merthyr Lines
Penarth and Rhymney/Bargoed - incorporating the Vale of Glamorgan and Rhymney Lines
Radyr and Coryton - incorporating the City and Coryton Lines
Cardiff Central and Treherbert - incorporating the Rhondda Line only
Cardiff Queen Street and Cardiff Bay - incorporating the Butetown Branch Line only
Surrounding lines
The following lines also serve Cardiff and the South Wales Valleys but are not considered part of the network by Transport for Wales and use more "mainline" rolling stock (currently Class 170 units).[citation needed]
^Cardiff Central and Queen Street are where all services pass through and are interchanges to the national network. Pontypridd and Barry are the two stations with the largest passenger numbers outside of Cardiff and they are only served by this network. See respective Wikipedia pages.