Jan. 14, 1967: The Human Be-In
The Summer of Love actually got its start in the winter, with an event at San Francisco's Golden Gate Park known as the "Human Be-In," which drew 10,000 hippies to sing, watch performances and listen to speeches by people like Timothy Leary (seen here) and Allen Ginsberg, who, TIME remarked that year, had "survived the transition from beat to hip."
"Not a single fight marred the Be-In, and as the sun went down (to the sullen wail of Ginsberg blowing a conch shell), the forgathered hippies quietly cleared every bit of litter from the park," TIME wrote. "Officials later said that they had never seen so large a crowd leave so clean a field."