Grand Prismatic Spring

— Besides being the first national park in the world, Yellowstone National Park is well known for its myriad number of hot springs, mudpots, fumaroles and geysers. Established on March 1, 1872, the park area covers 2.2 million acres. Yellowstone is a biosphere reserve and a world heritage site spreading across portions of Idaho, Montana and Wyoming. The Grand Prismatic Spring is located in the Midway Geyser Basin. According to the National Park Service, “a geyser basin is a geographically distinct area containing a “cluster” of hydrothermal features that may include geysers, hot springs, mudpots, and fumaroles.” The Grand Prismatic Spring is approximately 250 x 380 feet (76 x 116 m) and is the largest hot spring in the park and the third largest in the world (the first two are in New Zealand). The photo here shows the outer area of the spring. The colors in the center are deep blue and become pale blue towards its edge. The beauty of the spring can better be appreciated by aerial photography. Surrounding the blue center, there are various shades of yellow fading into orange and then red. Steam, as shown in the photo, is often present. This spring discharges approximately 560 gallons per minute.