Ok If your coming from the bay area you take 580-120 through tracy/manteca to 99 south and exit Jack Tone Rd in ripon(flyingJ and loves truck stops). Left on jack tone off 99 and look for the big soccer ball (river Rd). We usually start showing up around noon and park right in the first park entrance. I try to get there around 10 but my other half doesn't always make that possible
Ends sometime around 6pm. Bring a picnic lunch and drinks or you can hit one of the food places right off the freeway.