Luke Bryan, Reba McEntireTim McGraw and many, many more have lent their voices to "Forever Country," an all-star single released to celebrate the 50th anniversary of the CMA Awards.

“Forever Country” is an impressive medley of John Denver‘s “Take Me Home, Country Roads,” Willie Nelson‘s “On the Road Again” and Dolly Parton‘s “I Will Always Love You," produced by CMA Award-winning songwriter Shane McAnally, who calls crafting the mashup "a very scary process."

"I didn't think it would work in our genre," McAnally admits to People. "I said, 'Maybe in pop music you can just take a piece of a song, but we tell stories. And we can't just cut into them and take a piece.'"

However, as the idea began to take shape, McAnally saw how the iconic songs could all work together.

"When you play ["I Will Always Love You"] over "Take Me Home, Country Roads," they somehow take on a life together, and it feels almost like you're speaking more to the music, and to country music specifically, when you say, 'I will always love you.' It feels meant to be," the songwriter explains, adding that, when it came to "On the Road Again," "The line 'The life I love is making music with my friends' kept coming into my mind, and "On the Road Again" felt essential."

Readers can press play below to hear "Forever Country," which opens with West Virginia native Brad Paisley singing the beginning of "Country Roads." From there, bits and pieces of the medley are sung by Keith Urban, McGraw, Faith Hill, Kacey Musgraves ... and, yes, Nelson and Parton, too.

"I was very scared when Dolly heard it that it might seem like a bit of a compromise to the integrity of the original song. The song is such a simple, perfect sentiment. It was really important for her to know we handled it with care," McAnally confesses. "She just listened and said, 'Wow. That really works!' It was really hard not to cry in front of her. I've cried a lot since then!

"The responsibility of this feels greater than anything I've done," McAnally adds. "I hope this is a great timepiece for the legacy of country music."

"Forever Country" is available for download on iTunes; proceeds will go to the CMA Foundation's music education work. A full-length music video, directed by Grammy Award-winning director Joseph Kahn, will premiere on Sept. 20.

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