A major milestone, to extend the DART line to Meath and Kildare, is being reached this week.
A planning application is being lodged that will mean faster and more frequent trains for places like Castleknock, Leixlip and Maynooth.
Emma Tyrrell has more from Ashtown, one of the stops on the line:
Under this plan the dart will be extended from Connolly and Spencer Dock in Dublin - out to Maynooth and the M3 Parkway in Meath.
The number of trains running per hour will double from 6 to 12 - while passenger capacity will almost triple.
But it will involve closing six level crossings - including the one here in Ashtown (pictured) near the Phoenix Park.
Mark Gleeson from Rail Users Ireland says it could cause issues in Coolmine and Clonsilla.
"It's a year behind schedule already, I encourage people to take a read of the documents and try to help."
"Obstructing this is not helping anyone."
Barry Kenny from Irish Rail says its hoped work can begin in 2024, becoming operational in 2029 - and will involve a number of aspects;
"Building new entrances to Connolly Station and also re-locating the docklands station."
Potentially impacted landowners and occupiers are be contacted directly before the application is lodged on Friday.
