The roof of Pearse Station in Dublin's to be replaced, with major works kicking off this Bank Holiday weekend.
Iarnród Éireann says the roof structure, which dates from the 1880s, is in poor condition.
While track works mean DARTs are suspended between Connolly and Dun Laoghaire, and between Bray and Greystones today and tomorrow.
Iarnród Éireann spokesperson Barry Kenny says a lot of work lies ahead for fixing Pearse Station's roof.
"The Pearse roof replacement is a major project to replace what is a 19th century structure which is now life expired," said Mr Kenny.
"That means, in particular, over the next two years there will be disruption on a total of no more than 13 weekends.
"This is the first weekend and together with line works at Lansdowne Road it means that on Saturday and Sunday there will be no services between Connolly and Dun Laoghaire and Dublin Bus will accept rail tickets for that area."
October Bank Holiday— Iarnród Éireann #StaySafeSaveLives #HoldFirm (@IrishRail) October 27, 2018
⚠️No trains Connolly-Dun Laoghaire (Sat & Sun) or Bray-Greystones (Sat to Mon)
❗️Check your timetable for other Bank Holiday changes
🏃♀️Pre @dublinmarathon trains from Howth, Maynooth, Drogheda
🕑Clocks go back tonight
Full info: https://t.co/r50m2431AZ pic.twitter.com/nYt04D6N46