A Walk in the Woods / U.S.A. (Director: Ken Kwapis, Screenwriters: Rick Kerb, Bill Holderman)
An aging travel writer sets out to hike the 2,100-mile Appalachian Trail with a long-estranged high school buddy. Along the way, the duo face off with each other, nature, and an eccentric assortment of characters. Together, they learn that some roads are better left untraveled.
Cast: Robert Redford, Nick Nolte, Emma Thompson, Mary Steenburgen, Nick Offerman, Kristen Schaal.
Premiere is at … Sundance. No surprise.
Redford is Bryson. Nick Nolte is Katz. 🙂
besthike.com 
I ready the book several years ago. It’s a terrific book, looking foward to checking out this movie!