There was a time when country radio was about as likely to play anything by Old Crow Medicine Show as they were to play a cut from the new Slayer album. No mainstream country station that was interested in staying on the air would have thrown this old-time Americana string band onto their airwaves between Kenny Chesney and Blake Shelton.

And truth be told, even though they’ve moved from their native Virginia to Nashville, Old Crow Medicine Show still isn’t at the top of any commercial country radio playlists. The band, led by singer and multi-instrumentalist Ketch Secor, is far too ragged and rustic for that, as they have been for their 20-year career. In a sense, they still play the same hybrid of folk, bluegrass, and old-time music that they did as buskers on a street corner, which is what they were doing when they were discovered by the legendary Doc Watson in North Carolina back in 2000.

But whether you know it or not, you’ve heard a song by Old Crow Medicine Show on country radio a million times. Sure, it was probably Darius Rucker singing it, but “Wagon Wheel,” the most inescapable country song on Earth for years before “Old Town Road” came along, was co-written by Secor, inspired by an unreleased Bob Dylan bootleg from the 1970s.

The roots of the song actually date back much further; when Dylan sang, “Rock me mama like a wagon wheel,” on the bootleg (Secor built the rest of the song around that brief snippet), he was reaching back to mid-20th century performers like Big Bill Broonzy, Arthur “Big Boy” Crudup, and Curtis Jones.

But 80 years or so down the line, Old Crow and Rucker’s versions went platinum in 2013 and 2014, respectively, and suddenly an old-timey string band was in vogue in Music City, becoming Grammy-award-winning members of the Grand Ole Opry, playing multiple shows at the famed Ryman Auditorium — sacred ground for country music.

“Now thanks to Darius, mainstream radio had this surprise thrown on them,” Secor says, “and country music had to deal with us. It had to deal with this song that took a century to go number one.”

As Old Crow Medicine Show has gone from street-corner busking to selling out theaters, Secor says the band’s role in the bigger music industry picture has changed as well.

“I feel like we’re a governing agent in country music that is present to remind everybody about what this music started out being,” he says. “The fact is that we were never supposed to be a mainstream country band, but we found this bizarre mainstream success with a song that’s essentially the new ‘Wabash Cannonball’ or ‘Rocky Top.’ The best part of that for me is that country radio had to contend with real, genuine country music. There’s nothing like that on the radio today. With our fiddles and banjos, it reminds country music makers that this is how it started.”

That statement might sound grandiose, simply because pure-country, acoustic-based songs still aren’t the norm on mainstream country radio. But in terms of career momentum, it’s difficult to deny that Old Crow Medicine Show has essentially been moving upward since 2013 or so. Their most recent studio album, 2018’s Volunteer, crashed the Top 15 on Billboard’s Country Album charts at around the same time it hit No. 1 on the Bluegrass charts, and they’ve been able to pack the Ryman Auditorium (along with other theaters around the country) for the last seven years or so.

Last year, the band compiled highlights from those Ryman shows into an explosive in-concert album called Live at the Ryman. The album is a blast of a fun-loving, visceral collective energy from the performers and the crowds.

“It’s one of these venues that has a lot of ghosts,” Secor says. “It’s haunted in all of the right ways, and that haunting is sort of the fifth Beatle on this album. You can feel the room and hear the shape of it. It moves; it reverberates, the audience has a hum to it. It feels like a secret weapon to be able to make an album at the Ryman.”

Speaking of secret weapons, even after the glow of “Wagon Wheel” has faded away, Old Crow Medicine Show can still fall back on their feverish, intense live shows. They make a hell of a noise for an all-acoustic band, and Secor says that that no-holds-barred style has been in place since their street-corner days.

“Our time on the curb was foundational for us as a band as we figured out what our sound was,” he says. “The adventure of being in this band, particularly about 15-20 years ago, was a wild vibe. We walked into places, set our cases up, and we were either showered with coins or asked to leave or taken to holding cells. It could’ve gone any which way. We were kings and paupers and anything in between.”