Stern Grove Festival in San Francisco
Since 1938, the Stern Grove Festival has offered free Sunday concerts in a eucalyptus-ringed natural amphitheater in San Francisco, making it the oldest continuously running free performing arts series in the United States. Summer Sundays bring a mix of orchestral, dance, and popular music programming, including the San Francisco Symphony and San Francisco Ballet, without any admission charge.
Its historic free-concert model gives it clear cultural importance beyond ordinary shows.