Emile Hirsch

Christopher McCandless / Alexander Supertramp

Marcia Gay Harden

Billie McCandless

William Hurt

Walt McCandless

Jena Malone

Carine McCandless / Additional Narration (voice)

Brian H. Dierker

Rainey

Catherine Keener

Jan Burres

Vince Vaughn

Wayne Westerberg

Kristen Stewart

Tracy Tatro

Hal Holbrook

Ronald "Ron" Franz

Thure Lindhardt

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