The cave mentioned above is a collapsed lava tube. You can reach it by navigating 300 degrees from the old pier pylon that everyone ties their flag to. The cave is just a small part of a very nice reef with lots of structure. Turtles and occasionally white tip reef sharks can be found here. I've also encountered spinner dolphin on the surface in this area during the spring. You can reach this from the next beach down; Farrington also, but it's about the same swim either way.