Irish Rail is banning people from drinking alcohol on some of its routes from next week.
The ban will come into effect from October 12, and will be enforced every Friday, following regular reports of anti-social behaviour connected to excessive alcohol consumption.
It will affect the Heuston to Galway routes departing at 11:25, 13:25 and 15:35; as well as the 14:45 train from Heuston to Westport.
No alcohol will be sold by catering staff on the carriages, while customers caught drinking their own will have it confiscated.
"The vast majority of customers who wish to enjoy an alcoholic beverage on-board our services do so without impacting in anyway on their fellow passengers, but unfortunately there is a minority that do over indulge, particularly those travelling in large groups, who can disrupt others in a negative way," a spokesperson for Iarnród Éireann said.
"There have been high volumes of complaints of such behaviour on these services so we have taken the decision to ban all alcohol from them."
There are a number of Irish Rail services that have been alcohol-free for some time.