Work on installing an €8 million signalling system to control operations in Kent Station, Cork and on approaching lines, is due to get underway later this month.
Irish Rail has warned it will cause disruption to train services to and from the station for up to 11 days, with a replacement bus service in place temporarily from 16 October.
The new signalling system will replace a mechanical signalling system dating in part from the early-to-mid 20th century.
The computer-controlled interlocking system is part of major improvement works being undertaken to facilitate future plans for a suburban commuter rail service to run between Mallow, Cork, Cobh and Midleton by 2026.
The company says the new system will improve safety, punctuality and provide uninterruptible power supplies on the lines running to and from the country's second biggest railway station.
It will also facilitate connection to the new National Train Control Centre at Heuston, currently under construction.
Yesterday, the National Development Plan confirmed €165 million for Phase One of the Cork Commuter Rail Service which includes the provision of six new railway stations.
The work being undertaken this month will also facilitate the future double track layout modifications required for this new suburban service.
Essential track works will also take place at a number of locations between Mallow and Cork including the renewal of two crossovers in the Cork Tunnel, and track excavation and relaying works at Mourneabbey and Rathpeacon.
To facilitate this work, rail services will be suspended between Cork and Mallow and bus transfers will be put in place on both directions of the Cork/Dublin Heuston and Cork/Tralee services, from 16 October until 26 October.
The weekday 6.15am Cork to Heuston train will be cancelled.
Separately, from Saturday 23 October for three days, a bus service will replace the Cork to Cobh and Cork to Midleton service.