The figure you see scratched into the rock just to your left from the top of the sign was created by the ancient Chamorro. It is thought to depict a person in a boat. Inside the main part of the cave is evidence that people frequented Kalabera as long as 1,200 years BEFORE CHRIST. I have not heard an estimate to the age of this particular boat etching. I can probably guess with much more accuracy when Dennis loved Tomoko and James loved Jave. Seems a shame that people deface such things. On the other hand, who knows for sure that the folks who etched the boat weren't just graffiti artists who came a bit earlier?