"Explore the coral-reef wonders of the Northwestern Hawaiian Islands at this free and incredibly family-friendly center on the Big Island. Interactive displays include a volcanic exhibit, a submersible with robot arms, and a huge 3,500-gallon saltwater aquarium that showcases the incredible diversity of fish found in one of our last truly wild places. The displays go a long way toward understanding why the spectacular waters of the Northwestern Hawaiian Islands, also known as the Papahānaumokuākea Marine National Monument, have been designated a UNESCO World Heritage site. Open Tuesdays through Saturdays, this downtown Hilo highlight also includes ample information about monk seals, one of the most endangered marine mammals. Only about 1,400 remain, and their population continues to decline."