In an effort to be part of a growing trend of organized "Love-In's" during 1967 starting with San Francisco's "Human Be-In", the local "In Crowd" produced the event without permits and/or permission and included musical groups Blues X Five, The Lost Souls and Hydro Electric Streetcar. They found an electrical source close to a picnic area, plugged in and played causing an uproar with the Parks Board. This was finally addressed a few weeks later when Mayor Hugh Stephen and council gave in to public support/pressure and overruled the existing policy allowed the city's first "official" Love-In at the Cameron bandshell on May 21, 1967.
For physical events that happen at a specific time. For example a concert, or dance performance. If there are multiple shows, you can still duplicate your event to cover them all.