Boulder Field is a really neat place, so much so that it has been named a National Natural Landmark. While there is a dirt road that can take you to it (from near the Hickory Run SP office), you can also hike there. The trail is about 3 miles each way: it's an out-n-back. Maybe not the most spectacular hike around, but still a nice walk in the woods, and a great payoff at Boulder Field. Plus you come out to the BF on the other side from where most tourists drive to it, so you get a totally different perspective on it. After hanging out there for a while and enjoying the amazing boulders, the hike back might be a bit anti-climactic, but at least it's flat and even a little downhill... <br />
There's a JTX guide service that does a 'best of Hickory Run' tour which includes several hikes in the park, and a visit to Boulder Field by either hike or car (depends on what other hikes are included). If you don't know the area, this might be a good option.
parking lot on Route 534 near underpass where PA Turnpike goes overhead. parking lot on north side of road, across the street from Hawk Falls trailhead parking lot
http://www.tripleblaze.com/trail.php?c=3&i=1352