Hippie Hill's fame dates to the mid-1960s, when the Haight-Ashbury neighborhood on the park's eastern border became the epicenter of the American counterculture. The hill's proximity to the Haight made it a natural extension of the neighborhood's psychedelic culture -- a green space where people could gather freely without the constraints of indoor venues. The Human Be-In of January 1967, held in the Polo Field deeper in the park, drew national attention, but Hippie Hill was the daily gathering place, the spot where the counterculture lived its ordinary life between the headline events.

The hill's informal traditions have outlasted the era that created them. Drum circles form on weekend afternoons, their rhythms audible from the tennis courts and Robin Williams Meadow. April 20 -- 4/20, the unofficial cannabis holiday -- draws enormous crowds to the hill, a celebration that has persisted through decades of shifting marijuana laws. The hill provides views overlooking Robin Williams Meadow and is bordered by oak and pine trees that frame the space. On any given afternoon, the population of Hippie Hill might include yoga practitioners, bongo players, tourists photographing the exact spot where they imagine Janis Joplin once sat, and dog walkers who live three blocks away and come here every day.

Hippie Hill carries its history lightly. There is no monument, no interpretive sign, no ranger-led tour explaining what happened here. The hill's significance is maintained through use -- the fact that people still come, still spread out, still play music and lie in the sun. It is the opposite of a museum: instead of preserving the past behind glass, Hippie Hill keeps the past alive by continuing to serve the same purpose it always has. The grass grows, the fog comes and goes, the drum circles form and dissolve, and the hill absorbs another generation of San Franciscans who think they discovered it first.