The knoll used by Gregg's brigade at Second Manassas is indeed within the park boundaries. If you walk along the unfinished RR from Sudley Church about .5 mile, you will come to a narrow opening where a gas line crosses the excavation. That gas line crosses directly over the knoll used by Gregg. Coming from the church, it does not appear to be a knoll, but coming from Featherbed Lane it clearly is. I hope this helps.