What started as a small bluegrass fest 36 years ago has morphed into what may be the season's best party, with a setting—an amphitheater planted beneath a cirque of fourteeners—that's without equal. The vibe is no longer just bluegrass; it's more like a rock concert in the mountains, with some 10,000 fans per day.
Don't Miss The Punch Brothers; Three Girls and Their Buddy (Emmylou Harris, Patty Griffin, Shawn Colvin, and Buddy Miller), and headliners David Byrne and Elvis Costello, whose backing country band includes fiddle virtuoso Stuart Duncan. Tip: The best shows often take place after hours, in the NightGrass series at bars like Fly Me to the Moon Saloon (from $15; bluegrass.com). Four days, $185; bluegrass.com.
Intermission Take your mountain bike and ride Mill Creek, a six-mile singletrack loop just outside of town.