Jack and Rachel of Grooveshark.com at Rothbury Music Festival 2008. The Rothbury Music Festival was a four-day music festival in Rothbury, Michigan, at the Double JJ Ranch. The first year of the festival occurred over the July 4th holiday weekend, 2008. The festival is intended to promote sustainability and promote overall improvements to the environment. AEG Live and Madison House Presents are producing The first news of the festival was released on February 13th along with the initial lineup. It has been hailed as a great success with an estimated 50,000 in attendance.