Relevant to the roots of the hippie movement/ flower power in the 60's. Specifically, this is the area around the intersection of Haight st. and Ahsbury st. 60's legends like The Grateful Dead, janice joplin all lived around the area.
A fun store to buy hippie psychedelic souvenirs from would be the Ashbury Tobacco Center.
Or take the Hippie Walking Tour -
just google 'Haight Ashbury Flower Power Walking Tour'