This September, Mix 104.1 is bringing quite the party to the DCR Hatchshell. MixFest 2013 will take place on Saturday, September 14, and the lineup was announced this morning on the Karson and Kennedy radio show. Are you ready for this one?

The Backstreet Boys, Of Monsters and Men, and Gavin Degraw are on the bill for this year’s fest — which, by the way, is absolutely free, as usual. Draft up your plan of attack early: you’ll want to make it to the Hatchshell for this, but so will the rest of Boston.

This MixFest is sure to be a blast with Of Monsters and Men, who played a great set at this May’s Boston Calling Music Festival; The Backstreet Boys, who are making your elementary-school dreams come true; and Gavin Degraw, who … did the theme song of One Tree Hill.

So mark your calendars, pack up a picnic basket, and pull out your I <3 NICK CARTER T-shirt.

Want to get even more pumped? Check out this video of BSB performing “Larger Than Life” at the Bank of America Pavilion on August 12.