SummaryCalifornia Mid-State Fair is happening from 18 July 2018, Wednesday to 29 July 2018, Sunday at Paso Robles Event Center in Paso Robles, CA. The organizer of the event is California Mid-State Fair Board. The event is open to public. The estimated number of attendance is 420,000. The frequency of California Mid-State Fair is annual. The event has been running since 1946.