80,000 people are expected to attend tonight's gig.
80,000 people will head to Croke Park later for the first of Garth Brooks' five concerts.
Gates open at five o'clock, with the shows starting at half seven.
Extra public transport has been added for the gigs this weekend and next.
Event controller, Eamon O'Boyle, says a unique stage has been built to accommodate GAA HQ, which has a bigger pitch than most stadiums;