No they don't. The trails are not wheelchair friendly! That said I have seen several scooters handle it.
Accessibility is listed on the website under Rules of the Realm. Having personally experienced ADA accessibility, wheelchairs, either electric or manual can be "doable". Keep in mind that surfaces are natural earth. If it rains, or has rained, it can be very muddy in general and hard to maneuver through.
Not that I am aware of. The terrain of the forest is not that wheelchair friendly though, most shops I can think of have wheelchair ramps, but as a whole the fair has dirt paths up and down a hill.
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