Rausch Creek offers GREAT offroading with camp access (tents/campers)... And as noted above, a ton of great areas in Sullivan County.
My family owns two cabins in the World's End area (one in Hillsgrove and the other in Estella). There are tons of mountain access roads, that will keep you driving through the area all day if you wanted. It's a great area to get away from the normal schedule.
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