Yellowstone National Park is home to some 300 geysers. Old Faithful Geyser was named by an expedition in 1870 and referred to as ‘Eternity's Timepiece’. However it is not the most frequently erupting or largest geyser in the park. It is simply the most famous, exploding into the sky on average every 35 – 120 minutes. Old Faithful is part of the Upper Geyser Basin, which features an astonishing 150 geysers.
Grand Prismatic Spring
This is one of the most photographed of Yellowstone’s hot springs and it’s clear to see why. The largest spring in the park (and the third largest in the world), it’s also the most colourful with red, orange, yellow, green, and blue rings framing the steaming water. The spring is located in the parks Midway Geyser Basin.
Mammoth Hot Springs
This large complex of hot springs is one of the most visited areas of the park, boasting many individually named geothermal features including Poison Cave, Paperpicker Spring and Little Burper. Also in this area is the historic Fort Yellowstone and the newly renovated Albright Visitor Center.
Geologists believe that large volcanic eruptions have occurred in Yellowstone on an approximate interval of 600,000 years. The most recent of these happened around 600,000 years ago and ash from the massive explosion (a thousand times the size of Mt. St. Helens) has been found all across the continent. The magma chamber then collapsed, forming a large caldera. Part of this caldera is the 136-square mile basin of Yellowstone Lake.
The Other Grand Canyon
Formed by erosion over thousands of years due to wind, water and other forces of nature, the Grand Canyon of the Yellowstone stretches around 20 miles long and half a mile wide. This is one of the most popular hiking areas in the park and you can stop for photos of the dramatic cliffs and roaring water at various look outs along the way. Artist Point is the favourite of these.