Roll out of town during the dog days and drive up to Tennessee's Cumberland Caverns, home of the monthly concert series dubbed "Bluegrass Underground." Taking place 333 feet deep into the earth, this is underground music in its most literal sense. At a constant 56 degrees (talk about a cool down, y'all), you'll be escorted past pools and waterfalls into the "Volcano Room" where it all goes down. The good people who work there have somehow managed the not-so-small feat of lighting the place with a swaying chandelier that hangs from ... the ceiling? Some things can only happen by the grace of God, you know. Serving as a sort of unofficial opener to the Grand Ole Opry on Saturdays, this is advertised as a family-friendly event, so leave those cigars and flasks in the car. Russell Moore & IIIrd Tyme Out Band visit the caverns on June 2 and the Steeldrivers follow suit on Aug. 11. 1437 Cumberland Caverns Road, McMinnville, Tenn. 931-668-4396. www.cumberlandcaverns.com.