The Swallow Hill Music Association is celebrating its 30th anniversary Saturday night, with RootsFest Denver, an event known in previous years as the Denver Folk & Roots Music Festival. Shawn Colvin, Leo Kottke, the Boulder Acoustic Society and Joe Pug are among the performers. Also playing is the longrunning bluegrass group Hot Rize, currently consisting of Tim O’Brien, Bryan Sutton, Nick Forster and Pete Wernick. A Taylor Leo Kottke 12-string guitar, signed by Leo Kottke and estimated to be worth $3400, will be raffled off at the festival. The location is the Ellie Caulkins Opera House at the Denver Center for the Performing Arts. Tickets are available online or at the box office.