There's some top rope bolts sticking out of the top of a small cliff face near Castle Rock Beach (in Balgowlah Heights). While the rock in the area looks ok, most of it is quite sandy and mossy. There's also a good boulder on Castle Rock Beach that has a number of move up problems and a good traverse. The seaward side is under water at high tide, and all of the problems start off the sand, so take a mat if you don't like getting your shoes sandy. The beach is a good place for a swim in summer.