Incredible Nature

#2: The Yellowstone National Park

Yellowstone National Park is America's first national park. It has the Old Faithful and a collection of the world's most extraordinary geysers and hot springs.
The Old Faithful is a cone geyser. The eruptions of the geysers can shoot 3,700 to 8,400 gallons between (14–32.000 litre) of boiling water to a height of 106–185 feet (30–56 m) lasting from 1.5 to 5 minutes.
The vivid colors in the Grand Prismatic Spring are the result of pigmented bacteria in the microbial mats that grow around the edges of the mineral-rich water. The bacteria produce colors ranging from green to red; the amount of color in the microbial mats depends on the ratio of chlorophyll to carotenoids and on the temperature of the water that favors one bacterium over another. In the summer, the mats tend to be orange and red, whereas in the winter the mats are usually dark green. The center of the pool is sterile due to extreme heat.