Fairy Falls-Imperial Geyser

The trail crosses the Firehole River Bridge and continues north on the Fountain Freight Road (once known as National Park Avenue) as it makes its way along the south side of Midway Geyser Basin. Grand Prismatic Spring lies ahead on the right. This enormous spring measures more than 370 feet across and 120 feet deep, making it the second largest hot spring in the world. Notice its brilliant colors. Early visitors to the park were told it was "so dazzling that the eye cannot endure it." Most of the colors you see are caused by bacteria which thrive in the hot water. Certain types of bacteria are found in extreme temperatures, including boiling water. The less tolerant photosynthetic cyanobacteria (commonly called blue-green algae) survive in Yellowstone's thermal pools in temperatures up to 167deg F. At that temperature the algae is normally a light yellow color. The water cools as it moves farther from its source. Soon orange, red and finally green algae are found near the outer edge of the spring. Look closely, even the steam over Grand Prismatic reflects the brilliant colors of the pool. In 1839, mountain man, Osborne Russell described it this way, "At length we came to a boiling lake about 300 ft. in diameter... The steam which arose from it was of three distinct colors from the west side for one third the diameter it was white, in the middle it was pale red, and the remaining third on the east light sky blue..." At the 1.0-mile mark, the trail turns left, leaves the freight road and enters the forest. This area was dramatically affected by the fires of 1988. As devastated as this forest appeared, it was not dead. In fact, by some measures it was more alive than before. Yellowstone was covered by aging lodgepole pine trees. This "lodgepole desert," as some called it, supported relatively few species of plants and animals. The fires opened the overhead canopy and cleared the cluttered forest floor. Within weeks, grasses and other plant life began sprouting and small animals began feeding on the feast of seeds dropped during the fire. Eagles, hawks, and owls then moved in to prey on these vulnerable animals. Burned trees attracted insects that in turn attracted a variety of other birds. Stop and look for signs of new life. Listen for the sounds of a forest alive.At the 2.5-mile mark, Fairy Falls is reached. Fairy Creek shoots out over the edge of the Madison Plateau and plunges 197 feet into a peaceful pool beneath. Members of the 1871 Hayden Survey discovered the falls from the top of one of the nearby Twin Buttes. They named it for the "graceful beauty with which the little stream dropped down a clear descent."To reach Imperial Geyser, continue another 0.5 miles farther west along the trail. This geyser became quite active in the 1920s. Because of its size (80-foot bursts from a 100-foot crater) and importance, a contest was organized to give the new geyser a name. Soon after the name "Imperial" was chosen the geyser fell dormant. Imperial Geyser erupted again from 1966 through 1984. Today, it merely boils and overflows its impressive crater and waits for subterranean changes to call it forth once again. Follow Imperial's large runoff channel 0.2 miles to the east to find Spray Geyser. This colorful geyser lies just north of the channel and erupts frequently through several openings to a height of 6 feet. From the base of the Imperial Geyser, you can ascend the obvious path to get a birds-eye view of the Imperial Geyser, and if you keep going after the ascent, you'll also get an excellent view of Fairy Falls in its entirety. You can turn back when you see a lake on the left. The lake itself is nothing special in itself, but from there you get a nice view of the Fairy Falls and rocks that surround it. Note that the ascent is steep and good shoes and a can-do attitude are important here.When you are finished exploring, return to the trailhead via the same route you came.Thanks to guidebook author, Tom Carter, for sharing this trail description. To learn more about visiting Yellowstone, check out his book, Day Hiking Yellowstone.