The first thing that comes to mind when you hear the word ‘Yellowstone’ is probably Old Faithful Geyser. The second thing that comes to mind is probably ‘that really cool rainbow looking pool that I don’t know the name of.’ If you’ve ever opened Instagram, chances are you’ve seen a least a dozen pictures of this wondrous Yellowstone spring called Grand Prismatic Spring. Here’s how to get a good look at it yourself!
The deets: Grand Prismatic Spring, spanning 350 feet, is the largest hot spring in the United States and the third largest in the world. Named for its striking coloration, its hues match most of the colors in the rainbow: red, orange, yellow, green, and blue.
The colors are a result of the microbial mats around the edges of the mineral rich water. The amount of color depends upon the temperature of the water, among other things. I am not a biologist, so I won’t pretend to know all the ins and outs of how these microbes work, but I can tell you that there is an entire book in the Yellowstone Forever gift shop that talks about them all! It’s definitely worth a look.
So, how do you get to this place? Easy peasy. Drive to the Midway Geyser Basin and park at the Fairy Falls Trailhead. The trail is a 1.6 mile out and back, moderately trafficked trail. There are a couple of cool features right near the parking area. Several unmarked springs and the Firehole River give beautiful vistas before you even start your ascent to the Lookout deck. Follow the signs for Fairy Falls Trail and when it splits, stay left and follow the sign to the Prismatic Spring Overlook. Keep walking! The trail is lined with low pines and you will enjoy increasingly impressive views as you ascend to the observation deck.
Once you reach the Lookout deck and take your obligatory selfies, slip your phone in your pocket, take a deep breath, and absorb the moment. What an amazing place you have found! Can you believe the colors? I wonder what it was like discovering this place for the very first time eons ago?
Pro tip: the colder the weather, the more steam that will rise from the pool, clouding the colors a bit. For a more vibrant experience, go in the warmer times of the day.
Have you been to Grand Prismatic Spring? What did you think about it?