To get here, from Northern VA you take I-66W to I-81S. Get off at exit 225 onto Rt 275W. Go 5 miles, then turn right onto Rt 250. Go 15 miles and make a sharp right onto Braley Pond Rd. It goes awhile and turns into a dirt/gravel crappy road. After about 6 miles, you'll come to a T. make a right towards Elkhorn Lake and then just go straight the rest of the way there till you reach the end of the road.
In order to get to the cliff jumping spot, walk toward the dam and head to your left. There will be an old staircase. Take this up until you are level with the top of the dam. The trail to the left will take you directly to the rocks for jumping. The cliffs range about 30-45ftish. There is a sign that says no swimming though so beware. The place is rather beautiful though.