Transformation of the Core Valley Lines

We've started work on Metro, a modern integrated public transport which will transform the way we travel. Construction, engineering and infrastructure work is underway to upgrade our rail network so that it’s ready for Metro.


  • electrifying around 170km of track
  • upgrading all our stations and signalling
  • building at least two new stations.

We’re upgrading the railway lines to Aberdare, Coryton, Merthyr Tydfil, Rhymney and Treherbert. These lines are also known as the Core Valleys Lines and they’ll become an important part of the South Wales Metro.  A number of South Wales Metro projects have been part-funded by the European Regional Development Fund through the Welsh Government.

The majority of our work for the South Wales Metro is scheduled for completion in 2024. We're working with carefully selected partners to deliver this scheme and will do all that we can to be a good neighbour to the estimated 50,000 properties within 200m of our railway lines.


What progress are we making?

We’ve already started work on the South Wales Metro, with the construction of our new £100m depot and Metro Control Centre at Taff’s Well, Rhondda Cynon Taff. This will be home to our new Metro trains as well as 400 train crew, 35 maintenance staff and 52 Metro Control Centre staff.

We've also completed our first signalling and electrification phase. The first section of track between Cardiff and Pontypridd is now 'live', carrying 25,000 volts - the equivalent of 100 times standard household electricity.