Ключевые слова: adventure, cave, cave of the mounds, cave system, cavern, crystal formations, destination, dramatic lighting, exploration, formations, geology, geology education, illuminated, interior, landmark, lights, limestone, mystery, national natural landmark, natural beauty, natural history, natural wonder, nature, no people, peaceful, photo spot, public attraction, quiet, rock formations, rock texture, scenic, stalactites, stalagmites, subterranean, tour site, tourism, travel, underground, underground world, wisconsin,