Gov’t Mule and Warren Haynes Band have both joined the lineup for the first Interlocken Festival. This will be the first time Haynes performs with both projects on the same day. The news broke during Gov’t Mule’s co-headlining gig with Primus in Charlottesville, VA last night.

As previously reported, Interlocken will take place in Arrington, VA from September 5-8. Other confirmed acts include: Neil Young & Crazy Horse, Furthur, Widespread Panic, The String Cheese Incident, John Fogerty, Zac Brown and The Black Crowes.