Improved signalling, station improvements and faster trains are among the measures planned by Network Rail. Work to electrify the line between the Severn Tunnel and Swansea should be complete by December 2018, paving the way for bigger, faster and more environmentally-friendly electric trains.
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Missed out on Monday's 'Wales This Week, Dylan's Legacy'? Catch up here:
The two projects going head-to-head today are: For the Young at Heart and Y Gwndwn.