This 12-hour, six-part documentary, directed by Ken Burns and co-produced with writer Dayton Duncan, traces the evolution of national parks – a uniquely American idea – from  the mid-1800s to the present day. It explores the biographies of the remarkable people who helped create the parks and save them from destruction.  It’s narrated by actor Peter Coyote and features first-person historical accounts, read by actors including Tom Hanks, Andy Garcia, Eli Wallach, Sam Waterston, John Lithgow,  Adam Arkin, and Lee Stetson as Muir scholar and as the voice of John Muir.