Ключевые слова: acid, america, boiling, clouds, color, corrosion, danger, drop, erosion, geology, geysers, green, 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,