Ключевые слова: australia, australian, background, backlit, black, byaduck, cave, cavern, caves, caving, dark, earth, entrance, environment, exploration, fern, ferns, flora, foliage, formation, frond, geology, green, greenery, hole, landscape, lava tube, leaves, light, natural, nature, nobody, opening, plant, rocks, scenery, scenic, shadow, spelunking, sunlight, tunnel, underground, victoria, wild,