It is not the biggest of the local county fairs, and that's a good thing as far as I am concerned. The Arlington County Fair is smaller and easier to navigate and worth a trip. Its website isn't stellar but it does have the schedule of events posted. Wednesday is limited to outdoor activities only, while the rest of the fair includes indoor activities, too. We've bought local honey, admired local dance troupes, and seen award-winning produce. I must admit that the pig races are rather amusing, though you have to be willing to get there early to get a good view.
(Only slightly off topic, we made pesto with our own basil. My older son was positively thrilled by the idea.)