A monument to a culture and a three-day concert, featuring some vision-boggling split-screen editing that maintains your interest in between the rock and folk (yikes!) performances (there must be two dozen at least). The new director's cut is nearly four hours long. Believe it or not, Santana played here free and without a recording contract (Carlos was just 19)! They are a highlight, so is Jimi Hendrix, in a bittersweet performance after a rain delay to a waterlogged and sparse crowd; his feedback-laden, instrumental "Star-Spangled Banner" is a paeon to both the Vietnam war and electronic rock. Mind-altering is optional. 8* due to mediocre sound (and some folk music!), but still one of the best and most ambitious documentaries ever filmed.