The first electric train out of South Wales, the 0850 Cardiff to Paddington, departed on Sunday.
Interim Managing Director Matthew Golton said:
‘I’m really pleased to say that the final stage of the electrification bar the Severn Tunnel was completed yesterday, helping us to deliver more frequent services, more seats and quicker journeys for customers.
‘It was really important for me to be in South Wales to celebrate this landmark for our services.’
Over the Christmas and New Year period, Network Rail engineers worked around the clock from 24 December to 2 January to switch on the electricity running through the overhead line equipment between St Brides, Newport and west of Cardiff Central station, ahead of a final stage of testing.
Elsewhere over the Christmas period Network Rail engineers worked from 24 December to 2 January 2020 at the east end of Newport station to replace a significant amount of track, renew the switches and crossings which allows trains to go from one track to another, replace the surface edges of platforms two, three and four and make some adjustments to the overhead line equipment.
Final testing took place in the Cardiff area over the course of last week enabling GWR’s Intercity Express Trains to run on electric between Cardiff Central and London Paddington from Sunday 6 January.
Bill Kelly, route director for Network Rail Wales and Borders, said: ‘Christmas is the quietest time on the railway which is why our major engineering work takes place at this time of year.
‘We would like to thank passengers and our lineside neighbours for bearing with us over the festive period.
‘The results of the electrification work will be hugely beneficial for passengers for years to come as electric services begin on 6 January from Cardiff to London for the first time. The work at Newport railway has also improved the resilience and reliability of the railway for passengers, for years to come.’