A bid to reopen a railway line between Aberystwyth and Carmarthen more than 50 years after it closed has received more backing following a feasibility study.
The £300,000, two-year study found it could be brought back into use at a cost of £775m to rebuild.
The original line stopped at more than 20 stations, but was shut in 1965.
Traws Link Cymru, which launched its campaign three years ago to re-establish the 90-minute route, welcomed the Welsh Government's report.
Chairman Adrian Kendon said: "It clearly shows that this project is not pie in the sky and all now depends on the political will from the Welsh and UK governments.
"We are fully aware of the environmental constraints noted in the report, and despite the seemingly high cost, it's worth remembering that recent road projects in Wales have cost far more, such as the widening of the A465 Heads of the Valleys road at £850m, with over £1bn proposed for the M4 relief road around Newport.
"We firmly believe that this project is more worthwhile, as it would connect north and south of the country, rejuvenating communities and boosting the flagging west Wales economy."
A train journey without the proposed route takes about six hours, via Shropshire, Newport and Cardiff, but only about 90 minutes by car.
The Welsh Government has been asked to comment.