Transport for Wales (TfW) has started dynamic testing of its new Stadler Class 398 CITYLINK electric tram-trains on the recently electrified Valleys Lines. The trials mark an important step towards the next operational phase of the South Wales Metro and follow the completion of major infrastructure works between Cardiff and the Heads of the Valleys.
The Class 398 fleet forms part of TfW’s £800 million rolling-stock investment covering Wales and the Borders. Each three-car set accommodates more than 250 passengers and is equipped to operate under 25 kV overhead lines or on battery power, enabling seamless transition between heavy-rail and on-street tramway sections.
Infrastructure enhancements totalling over £1 billion have delivered some 170 km of electrification on the Merthyr, Aberdare and Treherbert corridors, supported by new track layouts, upgraded signalling and a purpose-built £100 million depot and control centre at Taff’s Well. The facility will maintain and stable all 36 Class 398 vehicles and oversee Metro operations.
Marie Daly, Chief Operating Officer at TfW, commented:
“This is another major milestone for us at TfW. We’ve already introduced our brand-new Class 756 trains onto the Merthyr, Aberdare and Treherbert lines to improve the experience for our passengers. We’re now excited to progress to the next phase of the project, testing our light rail tram-trains that will offer a turn-up-and-go service as part of the South Wales Metro.”
Andrew Gazzard, Head of Operational Readiness, added:
“Our teams now need to gain familiarisation and handling experience of the trains, and we need to embark on driver training later in the year. It’s a really proud moment for me and the team to be able to see these tram-trains on the network and we look forward to the next stage in getting them prepared for passengers.”
Driver training and network integration activities will continue throughout 2025, paving the way for the introduction of a high-frequency Metro timetable designed to improve capacity, reduce journey times and enhance accessibility across South Wales.
