The Fremont Solstice Parade happens every year in Fremont, on the closest Saturday to the actual summer solstice. For 2005 the date is Saturday June 18th.
From the Fremont Arts Council page:
- The Solstice Celebration is an outpouring of creativity and community, a time for shedding cares and inhibitions as summer arrives in Seattle. In our Workshops, artists and people who love art come together to create beautiful, funny, satirical, and memorable objects and performances. Ideas are developed into human-powered ensembles that move and groove together through Fremont as the street is transformed into a roving theater with thousands of spectators.
- At Gasworks Park, a picnic-style afternoon unfolds with family and friends relaxing on blankets. The day culminates with the rebirth of the sun through the grand spectacle of the Solstice Pageant, a community collaboration involving hundreds—artists, actors, dancers, musicians, and You!
It is reportedly common to see naked bicyclists and other fun stuff.
More info: Solstice Parade event page