Dolly Parton in white

Dolly Parton donated $1 million to coronavirus vaccine research. (Wade Payne/Invision/AP, File)

(FOX NEWS) -- Dolly Parton has provided the world with such iconic songs as "Jolene" and "I Will Always Love You," but fans will have to wait until 2045 to listen to the country star's "secret song."

The 74-year-old reportedly revealed in her new book "Songteller: My Life in Lyrics," that she has an unreleased, unheard track locked away at Dollywood's DreamMore Resort.

The idea for the surprise came from her team as a marketing project. The song is supposedly sealed in a chestnut wood box (built by her uncle) in a glass display case.

"It would be a song that will never be heard until 30 years from the time we opened the resort. They said, 'You’ll be long dead,'" Parton writes, according to Taste of Country. "I said, 'Well, maybe not. I'll be 99. I’ve seen people live to be older than that.'

"That's like burying one of my kids, putting it on ice or something, and I won't be around to see it brought back to life," the songwriter described. "It's just burning me up inside that I have to leave it in there."

Parton did reveal that the mystery song is recorded on a CD and there's also a CD player inside the chest... just in case.

"Hopefully, it will play and the whole thing ain't rotted," she joked.

"Anyway, it's kind of weird or strange that they would ask me to write this mystery song," she recalled. "I don’t know if I want to live to be 100 or not. But you never know. I might, and if I do, I’m going to be at that opening."

Dollywood opened in 1986 in East Tennessee. The theme park features rides, memorabilia, theaters and a water park and is one of Parton's proudest accomplishments.

"Dollywood is one of the greatest dreams that I've ever had come true," Parton previously told News 24. "I am so proud of that I can't even begin to tell you. Dollywood is real special to me."

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