PRIMAL Scream in the Silver Granite in Palmerstown, Mumford & Sons in the Baggot Inn and Mika playing a set in the Graduate in Dun Laoghaire, Arthur’s Day was as surreal as it was successful.
The last big band they hosted were the Dubliners when Ronnie Drew was at the helm.
Toner's on Dublin's Baggot Street was packed to the rafters for a show by English chart-toppers Mumford & Sons.
Security barriers kept the crowds back outside, while inside lead singer Marcus Mumford sipped a pint before his band struck up in front of 300 lucky punters.
"I'm flabbergasted. I've never seen anything like this," said Toner's owner Michael Quinn about the fan mania which had descended on his normally laid-back watering hole.
It was all part of the Guinness-sponsored Arthur's Day with gigs in 500 pubs across the land.
Glasgow band Texas played Limerick before setting off at breakneck speed for a late night gig in Galway.
Fun Lovin' Criminals turned up at Kazbar in Waterford city as Tinie Tempah plugged in at White's Tavern in Belfast.
A global audience also raised a toast to mark the anniversary of Arthur Guinness signing the lease on his brewery in St James's Gate in 1759.
Drinkers in the Graduate in Dun Laoghaire found themselves listening to a set from pop star Mika.
Meanwhile, the Silver Granite pub in Palmerstown, west Dublin, played host to Scottish rockers Primal Scream.
Local favourites the Coronas played in Charleville, Co Cork.
Other Irish acts included Royseven, Mundy, Picturehouse and Paddy Casey. No tickets were required for most gigs.