Very well marked and fenced closure areas, due to arsenic. The park is diligently working to clear it all up. PLEASE respect the closures, be safe, and have fun!
From the Penn Gate parking area, head up Hardrock Trail until you get to the 3-way(hub) intersection near Little Wolf Creek. Veer right and then right again and follow that up to the top of the hill. At the top of the hill, cut back left before the gate and head down the dirt road, it will soon taper into well groomed singletrack of packed crushed granite. Don't let your speed get away from you as the crushed granite goes from grippy to scary pretty quick. I think it's the park's way of reminding us that there is a 15mph speed limit, because thats about as fast as you'll want to go.