A major step towards the electrification of the South Wales Valley Lines took place this week as the electricity wires were switched on.

This is a major step forward and now allows Tri-mode trains to be introduced on the line to Rhymney.

It follows on from engineering work on the 25km stretch between Caerphilly and Rhymney, with the final section along the Cardiff Bay line being electrified in early 2026.

Transport for Wales, the operator of the line, has reminded passengers and the public of the serious risks caused by overhead wires, which carry 25,000 volts.

“The electrification of the Upper Rhymney line has been made possible by eight months of intensive work by our infrastructure teams, including installing 903 steel structures supporting over 33km of overhead wires and laying 30km of high-voltage cable. I’d like to thank our teams for working around the clock to achieve this major project milestone” 

“We would also like to thank our local communities for their patience as this transformation work was carried out through the day and night, as well as during disruptive railway closures over the Easter and Summer holidays.” 

Dan Tipper, Chief Infrastructure Officer at Transport for Wales