In the Hawaiian islands, the abundant petroglyphs are remarkably all similar in execution. Their common subjects include stick-like human figures, dogs, boats, sails, paddles, footprints, and ceremonial headdresses. Depictions of marine life, however, is rare, unlike the rest of Polynesia. They are typically carved into boulders, lava rock formations, and cliffsides. Red paintings of dogs in cliffsides and caves can also be found in Kauai and Maui. The megalithic traditions of Hawaii can be exemplified by the "heiau" sacred sites, which can range from simple earth terraces to standing stones.