People are being asked for their opinions on the proposed MetroLink in Dublin that will link Swords to Sandyford via Dublin Airport.
MetroLink, previously known as Metro North, is scheduled to be operational by 2027.
The plan proposes 25 stations, 15 of them brand new, and it is predicted that 15,000 passengers will use the service every hour during rush hour.
It also envisages the upgrading of the Luas Green Line to metro standard, which would link up to the metro services running north to the airport and beyond, to provide Dublin with “a high capacity, high-frequency cross-city rail corridor”.
Up to 4,000 jobs will be created during construction.
There are information evenings organised for people in Swords, Ballymun, Dublin City, Glasnevin, Ranelagh and Leopardstown.
National Transport Authority CEO Anne Graham said: "Thanks to MetroLink, there will finally be a rail link to Dublin Airport, and with easy interchange with other modes including bus, Dart and commuter rail, MetroLink will make it easier than ever to move into and around the capital.
“We have modelled future passenger numbers and we predict that capacity for 15,000 passengers per direction per hour during the busiest peak times will be required along this corridor. We don’t believe that a bus system or a standard Luas line would be able to accommodate that number of passengers and that is why MetroLink makes so much sense.
“MetroLink will have the capacity for 30 trains per hour in each direction, so there is no doubt that it will greatly enhance the public transport offering in Dublin."