DOVER - As the last reveler is just leaving the grounds Monday, Firefly Music Festival officials have already announced dates for next year's event. It will be held June 15-18.

A limited quantity of 2017 Firefly pre-sale passes will go on sale Wednesday at noon for $249. That is the same price pre-sale tickets, without a lineup of artists, went for last year. The price went up in 2015 for this year's event by $50.

This year's event drew an estimated 90,000 people and featured headliners Kings of Leon, Florence + The Machine, Deadmau5 and Mumford and Sons. Electronic music group Major Lazer officially closed the four-day event Sunday with a show that lasted until midnight.