There is a barbed wire unlocked gate/fence type thing that stays closed unless someone is passing through. Its right across from the prison farm on the dirt road who's number I'm forgetting at the moment.

Open the gate, drive through, close it behind you. There is a short narrow straight path with barbed wire on each side and another closed but unlocked barbed wire gate at the end. At that point you are on the trail.

An intersection is up there a ways, right there takes you to lots of big fun rocks but also a dead end. Left at that intersection takes you around to another intersection where there is a chain across a trail to the left. That's private property. Right takes you to the waterfall (Whale Rock).