Cole Swindell and Luke Bryan have a storied history together — one built on mutual admiration. When they embark on Bryan's Sunset Repeat Tour this summer, it'll mark a significant occasion.

The roots of this superstar friendship date back to Swindell's days as a student at Georgia Southern University, when he was only dreaming of becoming a singer-songwriter. Bryan also attended the university, and when he returned to his alma mater to play a show at his former fraternity house, Swindell knew that the then-unknown Bryan was destined for stardom.

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Flash forward nearly a decade, when Swindell made the move to Nashville to pursue his dreams. He started selling merchandise for his up-and-coming buddy on the road, and Bryan cut a few of his songs, including the hit "Roller Coaster." Swindell eventually graduated from merch sales to opening act on Bryan's That's My Kind of Night Tour in 2014, and, well, you know the rest of the story.

"I don't know if I'd ever written a song if I hadn't heard his music and met him and now look where it's taken us," Swindell says, thinking back on those early days and his friendship with Bryan. "To be able to go share that on the road ... I think he knows how excited I am and I can't wait."

Swindell has racked up eight No. 1 hits since his Georgia Southern days and headlined several of his own tours. But the Sunset Repeat Tour is something different — a way for him to return the favor to Bryan for years of support. He's so grateful.

"For him to believe in me at the beginning when I had one song, before that even, but now to be direct support, have Jon Langston out there, we're all family and we've been around each other for years," Swindell says. "This is something that I didn't know when it would happen, I didn't know if it would even, but I always thought for the last couple years even before I headlined I was like, 'I gotta go back out with him one more time, just like a big reunion one last time thing,' and I think that's what this is going to be. It's going to be a fun summer."

The Sunset Repeat Tour kicks off May 31 in Philadelphia and continues through October.

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