Jimi Hendrix’s final recordings are set to be released on a compilation, “Valleys of Neptune,” March 9 – nearly 40 years after the title track was recorded.

“Valleys” (the song) wasn’t released commercially, Rolling Stone reports. But it will officially drop as a single next month.

The album will also feature Jimi Hendrix Experience covers of “Bleeding Heart” and Cream’s “Sunshine Of Your Love.” “New” tracks include “Lullaby For The Summer” and “Crying Blue Rain.”

 “My brother Jimi was at home in the studio,” Hendrix’s sister, Janie, told Rolling Stone. “ ‘Valleys of Neptune’ offers deep insight into his mastery of the recording process …. His brilliance shines through on every one of these precious tracks.”