Mark out some time in 2009. PBS says it will air Ken Burns new documentary on America’s national parks sometime in the fall of that year.

The 12-hour, six-part documentary is called “The National Parks: America’s Best Idea”.

According to the Associated Press the series traces the origins and growth of the national park system over 150 years. The series will highlight both the lofty idealism that lead to their creation and the opportunism of some who sought to make money on some of America’s most majestic natural locales.

Tom Hanks, Andy Garcia and John Lithgow will voice some of the historical figures featured in the series. It will be narrated by actor Peter Coyote.

Burns’ documentaries are known for their comforting mix of archival photos, interviews, voice re-enactments and folksy period music.

Brooklyn, New York-born Ken Burns is probably America’s best known documentary filmmakers thanks in part to series like “Baseball”, “The Civil War”, “Thomas Jefferson”, “Frank Lloyd Wright” and the Academy-award nominated “Brooklyn Bridge”. The late historian Stephen Ambrose said of Burns’ films, “More Americans get their history from Ken Burns than any other source.” (They’re like a lullaby for insomniacs too and I say that with the utmost respect.)

Burns has an exclusive agreement to air his documentaries on PBS. That deal doesn’t expire until 2022.