No. You do not get in free for dressing up.
According to the flyer I got its open on weekends and Thanksgiving friday Sept. 30 - Nov. 26 9am - 8pm
Opening of each day is referred to as Opening Cannon, or just Cannon, which is 9 a.m. Closing is a bit flexible. On the top of the hour nearest dusk, they have fire works over the jousting arena. When they end, they fire the cannon and this is the signal for shops to close down, and for the guests to make their way to the exits. About 15 minutes later the security staff starts to sweep the grounds and sends stragglers towards the exits. * daylight savings time hits midway thru the run of the fair. On rare occations weather is severe enough for the faire to adjust it's hours, but this is rare indeed! They do not give discounts for being in a costume. You can find some discounts if you follow their facebook page in the spring.
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