Iarnród Éireann has predicted that this weekend will be one of the busiest of the year for rail travel.
While the Witnness event takes place in Kildare, many concert-goers are travelling to Dublin by train before making the journey to Punchestown.
Trains are also expected to be busy for the Munster football final between Kerry and Limerick in Killarney tomorrow.
Met Éireann is predicting good weather for the weekend, which will encourage more people to make journeys.
While extra trains have been laid on to cater for demand, Iarnród Éireann has asked intending passengers to buy their rail tickets in advance.
"This will help Iarnród Éireann plan their weekend operations and allow customers choose their outward and return trains in advance," said Mr Barry Kenny, Iarnród Éireann spokesman.
"Control cards" are being issued for trains to and from Dublin until Monday and also to and from Killarney tomorrow.
Passengers will need these cards with their rail tickets for today's Dublin-bound trains coming from Tralee and Cork/Mallow.
Tomorrow, intending passengers will need control cards with their tickets if they are travelling on certain trains from Dublin to Tralee, Killarney and Cork, and on the 6.16 p.m. train from Tralee/Mallow to Dublin.
On Monday, passengers travelling on certain trains from Dublin to Tralee and Cork will need control cards.
Full details of the arrangements are available on the Iarnród Éireann website - www.irishrail.ie - or from the company's passenger information helpline, 1850 366 222.
