Big Rock is in Maysville KY. It's HUGE! There is 2,000 acres of trails, open fields and so much more. You can ride down by the Ohio River, climb the widow maker, or fly across open fields.
The pic in my sig was taken at big rock. And unlike Haspin, 4x4s are not welcome. It's quads and dirt bikes only.
http://www.bigrockoffroadpark.com