The best way to get there is to get to Dublin, then use the festival bus to the site http://www.buseireann.ie. It costs around 25 Euros for a return ticket.
You can also get from Belfast by contacting email@example.com. You can also get a train to Portlaoise train station which is a 15 minute drive away, or get a festival bus for 4 Euros to the site, though there are not many running (check www.irishrail.ie for information).
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