From OC, get on the 91 East. From the 91 get on the 15 North. Exit on the 138 and go West, which is left. Take a right onto the 2 going up to Wrightwood. Stay on the two until you go through the tunnel. About 5 minutes after you pass the tunnel there will be a parking area on the right. Park there and take the trail down to the valley. There are climbes in the valley as well as on the rocks across the valley from the parking area. You'll know it when you see it.