On Sept. 30, Indigo Girls [ tickets ] will begin a fall tour, according the duo's official website, and on Oct. 3, the duo will release a greatest hits album, according to Epic Records.

Indigo Girls' Amy Ray and Emily Saliers will kick off their Honor the Earth tour on Sept. 30 in Billings, Mont. Bonnie Raitt [ tickets ], Indigenous [ tickets ] and Joan Baez [ tickets ] will perform at the tour opener, as well as at the Oct. 2 show in Great Falls, Mont., and the Oct. 3 show in Bozeman, Mont. An Oct. 4 show in Missoula, Mont., will feature Raitt and Indigenous, but not Baez.

Four late-October performances are then scheduled in the South, including a free performance in Atlanta on Oct. 28 at the Georgia Clean Energy Festival.

Proceeds from the upcoming tour will benefit Honor the Earth, an organization that raises funds for and awareness of Native American issues.

“Indigo Girls: A Retrospective” will feature 16 songs spanning the duo’s 15-year career, including its biggest hit, “Closer to Fine.” Two new tracks, “Devotion” and “Leaving,” will also be included. The album’s liner notes will feature a detailed, track-by-track commentary by Ray and Sailers.

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