Transport for Wales has electrified 99% of railway lines in South East Wales, marking a major step forward in the delivery of the South Wales Metro. Overhead wires on the Rhymney line were switched on at the weekend, shortly after His Majesty King Charles officially opened the new Taff’s Well depot.
Since 2023, the Rhymney, Treherbert, Aberdare, Merthyr, Coryton and Caerphilly lines have all been electrified, with the final section – the Cardiff Bay line – scheduled to go live in early 2026. The billion-pound Metro programme, often referred to as the ‘Welsh Tube’, introduced electric train services to the Valleys for the first time last year and will bring fully electric tram-trains into service next year.
Performance continues to improve across the network, with more than 90% of trains on the Core Valley Lines running to time in October 2025.
Ken Skates, Cabinet Secretary for Transport and North Wales, said:
“I am delighted that our investment of more than £1bn to deliver a metro system fit for the future has reached another significant milestone. Electrification of our core valleys lines is helping to create better access to jobs, healthcare, and education with brand new trains offering a faster, more reliable, greener and more accessible transport system.”
Julie James, Counsel General and Minister for Delivery, added:
“This is a game changer for many valleys communities, improving connectivity and making it easier for people to get to where they need to go quicker and without any hassle.”
Dan Tipper, Chief Infrastructure Officer at Transport for Wales, said:
“The electrification of the Upper Rhymney railway line signifies another major milestone for the South Wales Metro and delivering real change for the people of South Wales. It means that we’ll be able to introduce our Class 756 tri-mode trains on services between Caerphilly and Rhymney from 2026.
“Our infrastructure teams have worked intensively for the past eight months installing 903 steel structures, supporting 33km of overhead wires and laying 30km of high-voltage cable. This is a huge achievement for our teams, who have worked throughout the day and night to deliver these improvements.”
With the first electric trains already in service and Class 398 tram-trains set to follow next year, the Metro continues to reshape public transport across the region.
