Music in the Mountains Summer Fest has been an annual summer classical music festival in Nevada County, California since 1982. The non-profit organization, Music in the Mountains (MIM) holds events throughout the year in a variety of style for all ages. The artistic and music director was Hungarian conductor, Gregory Vajda from 2009 until 2016. Concerts take place in Grass Valley and Nevada City. MIM also sponsors Sierra Brewfest with many local microbreweries.