Iarnród Éireann has launched a public consultation on the possible extension of the Western Rail Corridor (WRC), north of Athenry, Co Galway.
The process is part of an ongoing effort to examine the economic benefits of running train services, firstly as far as Tuam and then on to Claremorris, Co Mayo.
The Programme for Partnership Government committed to "an independent costing and review" of the potential expansion of the rail line.
There are mixed views as to whether a train service would provide value for money.
Those in favour say it would take thousands of cars off the roads each day and provide much needed commuter transport for people living in north Galway and south Mayo.
But opponents claim the existing rail line should be repurposed as a Greenway to boost tourism and promote walking and cycling activity along the route.
Iarnród Éireann says it wants to get views from all sides, to get a "comprehensive understanding" of opinion on the proposals to extend the line.
It has appointed consultants to carry out the online survey, which will run over a six week period. It seeks public views on existing transport services, the extension of the rail corridor and any other observations people may wish to outline.
The company says the survey is only concerned with the proposed extension of the WRC and is not aimed at gauging opinion on alternative uses for the track.
The findings will form part of a wider overview to establish the value of extending the rail service.
This is due to be completed by the end of September, when the Department of Transport will conduct a further review before making any decision on the matter.
