At the top of the mountain behind the lodges, there used to be some big mud holes and a couple of off camber rocks you had to traverse. It connects with Old Bucktown Road and Nimbelwill Gap Rd. That intersection is also where the Appalachian (approach) Trail begins and it was the site of a small aircraft crash (there's a marker sign). I've got a pretty good map of the roads up there. Old Bucktown used to be the shizzle, because it was never maintained by the state or county, but the neighborhood (I suspect a prominent gun club) has been grousing at the FS for years over the hooligan traffic on those "trails". The neighborhood wanted Old Bucktown simply closed, but the FS said they would just take the fun out of it. They finally graded it and graveled it along with many other FS roads in the area. The park rangers at Amicalola have had problems with ATV's and that's what the no 4-wheelers sign is about. The park rangers are fine with full size 4wd vehicles and even condone you coming in and out of the park via the road you saw (thus circumventing the park fees).
http://goo.gl/maps/I84LL
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