Almost 60,000 people attended the Tennent's Vital music festival in Belfast this week to see Foo Fighters and the Stone Roses headline, organisers said.
The separate Belsonic promotion has also drawn thousands to acts including Madness and Thin Lizzy in Custom House Square.
Justin Green, a director at Tennent's Vital organisers MCD, said: "The event has had an extremely positive economic impact on the city, with not a hotel room to be had in Belfast.
"Our thanks go to PSNI, Belfast City Council and all the artists and crew who worked so hard but most of all to the 60,000 fans who yet again proved that Northern Ireland can host such a huge international event without incident."
Belfast City Council and the PSNI took more than 100 complaint calls about loud music from the Boucher Road playing fields venue in West Belfast.
Residents 15 miles away in places such as Comber and Dundonald reported hearing the Foo Fighters.
The concerts will continue today with local band Two Door Cinema Club, before Welsh singer Tom Jones takes to the stage on Friday and David Guetta at the weekend.