To repeat an earlier message: “Must view!!  The National Parks.“  Last night, I was sitting on the edge of my chair, tears running down my face.  My sincere thanks to Dayton Duncan and Ken Burns for that beautiful series (presented on PBS).  I’m positive I watched when it first aired in 2008; well worth watching a second (or third?) time. (Beauty in the middle of the night!! I watched two hours on one PBS station and then checked another [of five available] and watched their broadcast.)