Greensky Bluegrass with special guest Junior Brown The Ark and Bank of Ann Arbor present the Ann Arbor Folk Fest at Hill Auditorium. The festival is The Ark's largest annual fundraiser and delivers the full spectrum of “Ark music,” presenting a taste of what’s happening on the leading edge of acoustic music while delving into the very heart of folk and roots traditions. Friday night features a new format with a later start, and a concert length performance from Michigan's own Greensky Bluegrass.