Music, sport and film are among the main attractions in a weekend of events that has something for everybody.
The three-day music spectacular that is Oxegen officially gets underway this afternoon.
More than 30,000 fans descended onto Punchestown racecourse in Kildare for the festival yesterday.
But gardaí are estimating that another 35,000 will have arrived there by tonight.
AA Roadwatch expects the peak time for traffic approaching the site to be from 2pm to 7pm, and advises motorists to give themselves three hours more than their usual journey time to get there, with public transport being the recommended means of travel.
People arriving by car at the venue from this afternoon are being advised to use the park and ride facility at Goffs, Kill, Co Kildare rather than the venue carparks.
Other music highlights include American rapper 50 Cent being the final act to perform at the Live at the Marquee festival in Cork tonight.
However, for many the big event of the weekend will be the return to Ireland of Bruce Springsteen and the E-Street Band. The Boss will play the RDS in Dublin on Saturday and Sunday, with tickets still available for both concerts priced between €86.25 and €96.25.
Gates open at the venue at 5pm, with Bruce and his band taking to the stage at 7.30pm on each night.
Key sporting action includes the Munster hurling final in Semple Stadium in Thurles on Sunday, with Tipperary and Waterford set to start at 4pm.
Two hours earlier the Leinster football final throws in with Dublin playing Kildare in Croke Park at 2pm. The Curragh Horse Racing Festival also takes place this weekend, featuring the Darley Irish Oaks on Sunday.
Meanwhile in the west, the annual Galway Film Fleadh comes to a close on Sunday, with Hollywood actor Angelica Huston set to attend the screening of The Dead- John Huston's 1987 adaptation of Joyce's Dubliners, which will be screened at the town hall.
New Irish films such as Memoriaand The Secret of Kellswill also be shown this weekend.
Limerick city is host to the Shannon International Music Festival, which also concludes on Sunday. Highlights include Storms in the Night, a performance by the Irish Chamber Orchestra at the Franciscan Church in the city at 7.30pm tonight.
The Clonmel Junction Festival in Tipperary and the Earagail Arts Festival in Donegal also continue this weekend.
The Kinsale Arts Week in Cork begins tomorrow and runs until July 19th, with Songwriter Paul Brady performing in the 18th century Charles Fort on Saturday, while on Sunday the Kinsale Street Day promises free family fun.
However, this weekend’s weather plans to do little to improve the festivities. Met Éireann has forecast tomorrow to be a wet and windy day, with Munster and south Leinster getting the worst of the conditions.
Sunday will be a brighter day, but spells of sunshine are expected to be interrupted by showers throughout the day.