The Summer of Love was a major social phenomenon that occurred in San Francisco during the summer of 1967. As many as 100,000 people, mostly young people, hippies, beatniks, and 1960s counterculture figures, converged in San Francisco's Haight-Ashbury district and Golden Gate Park. More broadly, the Summer of Love encompassed hippie culture, spiritual awakening, hallucinogenic drugs, anti-war sentiment, and free love throughout the West Coast of the United States, and as far away as New York City. An episode of the PBS documentary series American Experience referred to the Summer of Love as "the largest migration of young people in the history of America".

San Francisco, officially the City and County of San Francisco, is a commercial, financial, and cultural center in Northern California. With a population of 808,437 residents as of 2022, San Francisco is the fourth most populous city in the U.S. state of California. The city covers a land area of 46.9 square miles at the end of the San Francisco Peninsula, making it the second-most densely populated large U.S. city after New York City and the fifth-most densely populated U.S. county, behind only four New York City boroughs. Among the 92 U.S. cities proper with over 250,000 residents, San Francisco is ranked first by per capita income and sixth by aggregate income as of 2022.