Petroglyphs teach us a lot about the history of Hawaii, some of which date back to the sixteenth century. Hawaiians call this form of rock art "images in stone". Some of the petroglyphs are clustered near historic land boundaries or along foot “highways” through lava fields, but the reasons for their creation remain a mystery. Both development and lava have destroyed many of these treasures. The Waikoloa Petroglyph Preserve follows a trail with images inscribed on lava rocks. Some are of humans, birds, canoes and others of dots or lines. The word petroglyph comes from the Greek words, 'petros' for rock, and 'glyphein' to carve.