Dolly Parton has recorded a secret song and locked it away in a time capsule for her fans to eventually hear in 2045.

The special track has been sealed away in a box made out of chestnut wood at Dollywood’s DreamMore resort, which she opened in 2015.

According to Parton, staff have been specifically instructed not to open the box until the 30th anniversary of the venue’s opening.

Announcing the plans in her book, Songteller: My Life in Lyrics, Parton explained how the plans were first mooted by her own marketing team.

“It would be a song that will never be heard until 30 years from the time we opened the resort,” she explained.

“They said, ‘You’ll be long dead.’ I said, ‘Well, maybe not. I’ll be 99. I’ve seen people live to be older than that.’”

While Dolly has added a CD player in the capsule, she admitted it has been “tough” to not touch her finished effort.

“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,” she said.

“It’s just burning me up inside that I have to leave it in there.”

Dolly added: “Anyway, it’s kind of weird or strange that they would ask me to write this mystery song. 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.”

The singer also recently revealed that she is considering selling the rights to her entire songwriting catalogue.