Ключевые слова: acid, america, boiling, clouds, color, corrosion, danger, drop, erosion, geology, geysers, green, hot spring, hot springs, landscape, limestone, limestone formations, mountain, natures, panorama, park, prairie, river, sky, spa, spry, steam, sulfur, summer, sun, tourism, toxic, travel, trees, united states, vegetation, water, wyoming, yellow, yellowstone, yellowstone national park,