Services between Portarlington, Galway and Dublin will be impacted.
Irish Rail is advising the public of a series of essential works in a number of locations around the country.
From tonight services between Portarlington, Galway and Dublin are affected.
Tomorrow works will take place between Limerick and Limerick Junction, Dublin Connolly to Dun Laoghaire and Cork to Midleton.
Irish Rail spokesperson Barry Kenny, explains why the upgrades are taking place over a bank holiday:
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