The Belsonic music festival kicked off in Belfast on Tuesday night with a performance by Kasabian.
Billed as Belfast's biggest music event this summer, some of the biggest bands will performing over the course of the event at Custom House Square.
Paolo Nutini, Paul Weller and Florence and the Machine are headlining as part of eight days of concerts.
Belsonic at Custom House Square in the city centre will also feature veteran Welsh rockers Stereophonics.
Other headline acts include 2manydjs, Biffy Clyro and David Guetta.
Promoter Alan Simms said this year's event was more ambitious than in the previous two years.
"It's almost quadrupled in size, so it's really quite exciting for us," he said.
"The crowd will vary: there's stuff for older audiences like the Stereophonics and Paul Weller, as well as pop acts like David Guetta and Florence."
Mr Simms said the success of previous years made it easier to attract big names.
"Once you have a tried-and-tested event, you can show bands' representatives a list of people you've had previously and there's more faith in the event," he said.
Lord Mayor of Belfast Pat Convery said the announcement was "fantastic news for local music fans".
"Belsonic is a fantastic festival for the city, bringing together international and local musicians to produce really exciting events in the unforgettable surroundings of Custom House Square," he said.
Local bands including General Fiasco, Cashier No 9 and Japanese Popstars will also perform over the course of the eight-day event.
Previous Belsonic headliners include Dizzee Rascal, the Zutons, the Flaming Lips and Duke Special.