It was filmed in 1973 on location at Mono Lake, CA (where I spent some of my High School time living
with my dad). I met Mr. Eastwood on the set (the day he was getting coached on how to properly crack that bullwhip).
Factoid: My sister Casey, a local "townie", was hired
as production secretary. It was on the set that she met her future husband, my brother-in-law, John Tiffin Patterson, who was an assistant director.
Before his passing in 2005, John went on to direct over 90 films and television shows, collecting the Director's Guild award (and several Emmy nominations), notably for the final installments in each season of The Sopranos.
We all miss John.
Incidentally, Mono Lake was also the location for the photo "The Diver" which appeared on Pink Floyd's album "Wish you were Here".
According to the Wikipedia entry, Mono Lake was also the setting for Mark Twain's Roughing It, published
in 1872. You can read it online at
(Check out chapter XXXVIII on page 259).