The Dart line between Bray and Greystones in County Wicklow will be closed for the day after a fire.
Signalling and telecoms cables were damaged when flames spread from a tent pitched away from the tracks.
Irish Rail's Barry Kenny says Dublin Bus will accept valid tickets until the line re-opens to passengers.
He said: "Greystones to Bray is closed. Greystones Dart services customers can use their tickets on Dublin bus services and it will also impact people travelling Dublin to Rosslare line so we are going to have bus transfers between Bray and Greystones for people travelling on those particular trains."
Dart services from Bray to Greystones are currently suspended due to a fire close to the line.
Fire Crew from Greystones are currently working to fully extinguish the blaze on Bray Head.
The fire started in front of a tent and spread along steep ground east of the cliff walk at around 1am this morning.
Affected Dart passengers are being advised that Dublin Bus is accepting rail tickets to and from Greystones.
The fire on Bray Head is under control unfortunately damage has been caused to railway infrastructure by the fire which is being assessed by Irish Rail.@IrishRail @GreystonesCC @wicklowcoco @BrayTCouncil #bray #WICKLOW @aaroadwatch @GardaTraffic pic.twitter.com/a4eytdpibg
— Wicklow Fire Service (@FireWicklow) July 13, 2018