3 hours from the Pinnacles Hut.
The Billy Goat Trail starts at the logging camp – instead of going right and heading for the stairs, you go sharp left after the stream (north-west), walk past the power company hut and follow the trail. This trail undulates again as it winds around the sides of the hills and there are some steep climbs but eventually it peaks and you can stop by an almost hidden information post and have a breather and admire the view.
The Billy Goat Trail used to have an old wooden bridged railway running from the top of the valley to the bottom. At about the ¾ mark (1½ hrs), there is a small marked diversion (trail) which can show you the remains of the main rail logging bridge. Alas, the bridge was blown up by army engineers thirty years ago when it was deemed unsafe, so there’s not much to see, but since your there you may as well look.
The trail becomes a gentle walk around the side of some more valleys (with remnants of train tracks and piles sitting about)…then the last half an hour will test the calf muscles…a step descent down to the valley floor. There are actually 2 ways down…Unless you know bushcraft, just follow the trail. It's wide and easy to follow (and steep). 30 minutes later you’ll cross the river and it’s a couple of hundred metres walk back up the road to the road-end (go right if you have just crossed the bridge / river), to the carpark.
The Stairs / Billy Goat trail can be used as a circular tramp. Some of the running clubs use it for training so don’t be surprised to see scantily clad anorexics charging around the place in their Nikes. They’re well behaved and will generally fall off a track rather than run you over.