Ключевые слова: active, active volcano, america, basin, caldera, ecosystem, firehole, firehole river, forest, geology, geothermal, geyser, hot, landmark, landscape, montana, mountains, national, national park, nature, outdoor, park, pool, rapids, red, river, rocky, scenic, spring, steam, steam vents, supervolcano, tourism, travel, usa, vents, volcano, water, wyoming, yellowstone, yellowstone caldera, yellowstone national park,