Irish rail is adding to its service for Christmas.
Iarnród Éireann has announced late night DART, Dundalk and Maynooth line commuter services are back from this Friday night, on the weekends in the run-up to Christmas, and after Dublin's New Year's Eve celebrations.
The company says it marks the busiest programme of late-night train services yet.
Meanwhile, drivers who use the M50 are urged to be patient, follow instructions from emergency personnel and listen to radio for information, in the event of a collision.
Gardai, Dublin Fire Brigade, Dublin City Council and Transport Infrastructure Ireland are explaining how they manage a critical incident on the motorway.
Traffic volumes on the M50 have grown every year since 2011 – and now stand at 140 thousand cars a day.