Several hiking and biking trails weaving around the hills between the 322 and 501. Some are tame, some near pro, all are very well kept and beautiful. Permits no longer required.
I recommend parking at pumping station road, heading south across the little bridge and going up the trail head there. Place has everything and is perfect for honing your skills. Major up-hills and down, but if you take the right path, you can get up one hill and be downhill for the rest of your ride.
Bart trail and Big Rock trails are hardcore, Sharp Valley trail is semi-tame and a lot of fun. You will get lost easily, but you'll find it fun to get lost because the area isn't really that big and you'll eventually get somewhere.