The Essential Guide to Grand Prismatic Spring, Yellowstone

Grand Prismatic Spring is Yellowstone’s star attraction. It attracts crowds from around the world to marvel at the vibrant colors of the largest hot spring in the United States. It’s an easy place to visit when driving around the Grand Loop Road of Yellowstone National Park but there are some tips to make your experience at Grand Prismatic more spectacular than simply pulling off and walking around the boardwalk.

How to Visit Grand Prismatic

Are you ready to visit Yellowstone’s most colorful hot spring? Let’s go!

If you are looking to have the best visit to Grand Prismatic Spring, read on to find out all of our tips and information to get the best views, learn when the most optimal time to visit is, and answer any other questions you have about visiting Grand Prismatic Spring.

Where is Grand Prismatic Spring

Grand Prismatic Spring is located in Midway Geyser Basin in Yellowstone National Park. It sits south of Madison Junction and north of Old Faithful along the Firehole River. It was named in 1871 by the Hayden Expedition after seeing it kaleidoscopic colors pop from the earth’s surface.

Midway Geyser Basin consists of remarkable prismatic springs including also Excelsior Geyser, and Opal Pool. When you visit Yellowstone, you must not miss seeing the natural wonders of Midway Geyser Basin. It’s the most photographed thermal feature in the park.

There is a large parking lot for Midway Geyser Basin, but it is often full and many people park on the side of the road. When we parked here we joined the queue of cars making their way to the parking lot. At first, we thought we made the wrong decision, but we were only in line for about 20 minutes.

It probably would have taken us 10 – 20 minutes to walk from the road, so It wasn’t too bad. Plus it was nice to be close to the hot spring when we finished so we could move on to Old Faithful and the Upper Geyser Basin sooner than later.

From the parking lot, you will follow the boardwalk that leads across Firehole River and takes you all around Midway Geyser Basin. It is forbidden to stray from the path. These geothermal features are very dangerous and fragile.

When to Visit the Grand Prismatic Spring

The best time to visit Grand Prismatic Spring is between May and September. Narrowing it down further, June to August will have less steam and let you see the colors even more vividly. When the temperature is cooler, the fog really builds up as the hot steam mixes with the cool air. So warm days will naturally give better views.

The best time of day to visit Grand Prismatic is between late morning and early afternoon when the sun is high. While crowds will be fewer in the early morning or late afternoon, you want to visit Grand Prismatic when the sun is shining bright because its rays really bring out the colors. Plus, the cooler temperatures of morning and afternoon create more steam and you won’t have as clear of a view.

You can visit it as early as April to November when the loop road is open. Check the National Park’s website for openings and road conditions.

We visited in September and felt that it would have been better on a warmer day. The steam was thick as it mixed with the cool autumn air. In the summer months, when the air is hot, the steam is less.

If you are spending more than one day in Yellowstone National Park, choose a day when the weather forecast is sunny and clear. We started our visit to Grand Prismatic on a sunny day, but when the clouds came in and it started raining, we saw the colors fade before our eyes.

Luckily, it was a windy day and the weather passed quickly. We waited it out until the sun came out from behind the clouds and saw that beautiful colorful view with our own eyes.

Can you visit Grand Prismatic Spring in Winter?

During the winter months, the only entrance that remains open in Yellowstone is the North Entrance. The only way to get around is via a snow coach or snowmobile. You can cross-country ski or snowshoe as well.

I have seen people claim that they went to Grand Prismatic during winter, but it looks a bit tricky to be able to visit Grand Prismatic in winter. I did find private multi-day tours that go to Grand Prismatic. It seems like the regular day tours mostly go to places like Mammoth and Upper Geyser Basin.

However, it can be done. In the winter, I would expect thick fog as the hot water clashes with the freezing temperatures. This tour takes you on an 8-day winter trip through Yellowstone and from what I could see is one of the few that goes to Grand Prismatic in winter.

What Causes the Colors of Grand Prismatic

Grand Prismatic may be beautiful and tempting to touch, but it is very fragile and dangerous. This giant hot spring is the largest in the United States and the third-largest hot spring in the world. The other two are in New Zealand and Dominica if you were wondering. Frying Pan Lake in New Zealand and Boiling Lake in Dominica is larger than Grand Prismatic Spring but they don’t hold a candle to the beauty of Grand Prismatic.

In the center of the spring, the water is 160 degrees Fahrenheit (70C), and because of this extreme temperature not many things (Even bacteria) can survive. That explains why the water is so clear. The light then scatters the blue wavelengths making it look a deep blue to the naked eye.

The colors of Grand Prismatic are comprised of bacteria microscopic organisms called thermophiles (I learned at Yellowstone that the name comes from the word, “thermo” meaning heat, and “phile” meaning lover.) In essence, these tiny bacteria are heat loving bacteria.

When millions of these thermophiles huddle together they create a colorful spring of different hues of yellow, green and oragne. The color of the bands depends on the type of thermophile and their tolerance for heat. The different color rings represent a different temperature, which attracts different organisms.

The inner band and most vivid blue waters of Grand Prismatic is the hottest. Not many things can survive in extremely hot water explaining why its core is crystal clear. As it spreads to the outer bands the temperatures cool and different species of microorganisms live in different high temperatures of water creating different colors of yellow, and orange areas.

The yellow band consists of bacteria that thrive in temperatures at around 149 degrees. The reds and rust colors are made up of a more diverse bacteria thus creating different hues of orange and reds. It’s all far more scientific than my explanation, so instead head over to the Smithsonian for a better understanding.

What It’s Like to Visit Grand Prismatic Spring

We grabbed a parking spot close to the entrance to Grand Prismatic. It was just a few steps from the parking lot until we were on the boardwalk and walking toward the famous hot spring.

The boardwalk is even and easy to navigate and is less than a mile long. To be exact, it is .8 of a mile (1.2 km) long and you walk it in a clockwise direction one way. The boardwalk of Grand Prismatic is accessible for wheelchairs and strollers.

What we love about many of Yellowstone’s attractions is that they are accessible. The boardwalk at Midway Geyser Basin is wheelchair accessible. There are no railings on the path though, so make sure to keep a hold of your stroller or walker when strolling around Grand Prismatic.

Even though it is busy at the entrance, we didn’t feel crowded during our visit. You cannot walk off the designated path, so really, we had unobstructed views of the area. If there was a cluster of people, we simply waited for them to move on. Plus, when looking over from the other side, it the people really helped to give scale to just how massive the mid-geyser basin is.

Other Hot Springs to See at Midway Geyser Basin

We spent about an hour walking around the boardwalk of Midway Geyser Basin. It could easily be done in 30 minutes, but this view is a once-in-a-lifetime experience, so we took our time not only studying the jaw-dropping views of Grand Prismatic but the other geysers and hot springs as well.

Excelsior Geyser Crater

The First Stop you’ll come to when walking around Midway Geyser Basin is Excelsior Geyser. As we walked up to the Excelsior Geyser a rush of steam hit our faces. The air was cool, but the steam was hot and we could feel the waves of hot and cold air pass through. At times it was quite thick and we could barely see, which made sense since Excelsior Geyser Crater discharges 4000 gallons (18,000 liters) of water per minute.

Combine the cool air with the heat from Excelsior Geyser and you have a wall of steam. Excelsior Geysers’ water temperature is a hot 99 degrees Fahrenheit (93 Celcius)

Watch our video as we walk through Midway Geyser Basin

The teal blue water runs into the nearby Firehole River creating blankets of steam along the riverbanks. Excelsior Geyser used to be an even more impressive geyser than Old Faithful, but it had its last eruption in the 1800s where it blew apart and left this massive pool of water. It is now simply a huge crater of bubbling hot water.

Grand Prismatic

The next stop along the boardwalk is to Grand Prismatic Spring itself. The walk along the path is interesting in its own right as it feels as if it is floating above a white sea. The trail then veers to snake along beside the massive hot spring. It is difficult to really take in the scope of this giant hot spring from here.

It’s so big that it is difficult from this vantage point to take it all in. It’s 200 feet (61 meters) across and you are basically eye level with it. We raised our hands and Gorilla pods as high as we could to get an overview shot of it. This is the busiest part of the walk and there are benches which we stood on (when nobody was sitting on them of course) to get a higher view. It still wasn’t high enough, but we’re going to show you how to see Grand Prismatic from above a little farther down.

Opal Pool

From Grand Prismatic you will continue on to Opal Pool. This is a small pool but it is colorful. As one woman said beside us, “Couldn’t I just take a photo of this and pretend it’s Grand Prismatic?” It does have the same characteristics indeed. It is a very pretty pool that is actually a geyser that erupts a couple of times a year.

Turquoise Pool

And finally, you will pass by Turquoise Pool. This spring is exactly what the name says. It’s a spring of clear turquoise water. If this were in another area of the park, it would attract a crowd but because it is right beside these colorful springs, barely anyone stopped to look at it. But look at it up there, it’s gorgeous!

Grand Prismatic Overlook

I know that we told you that we’d share how to see Grand Prismatic from above, and a hike to the Grand Prismatic Spring Overlook is the way to see the entire Grand Prismatic Spring and Midway Geyser Basin. This viewing platform is a 20 minute walk from the parking lot and lets you view the entirety of the largest spring in the US.

If you want to see an overhead view of the Grand Prismatic, we highly recommend the Grand Prismatic Overlook. This is the perfect view of Grand Prismatic Spring and the surrounding colorful hot springs from above (Without taking a helicopter tour).

If the sun is out and you see weather might be coming in when you arrive at Mid Geyser Basin, we suggest going directly to the Grand Prismatic Overlook before taking the walk about the Grand Prismatic Hot Spring below.

To get to Grand Prismatic Overlook trail, turn right out of The Grand Prismatic parking lot and drive 1.6 miles (2.5 km) to the Fairy Falls Parking lot. From the parking lot, walk over the bridge and follow the path.

The Walk out to Grand Prismatic Overlook takes about 20 minutes and it is uphill. The path is well-marked and easy to follow. When you come to a fork, you can also veer off to the right to see Fairy Falls. For the Grand Prismatic Overlook, take the path to the left and hike uphill.

This gravel path is not suitable for wheelchairs or strollers. It is considered an easy hike though and anyone in decent shape will have no problems reaching the overlook. The trail is only 1.2 miles (1.9km) long with an elevation gain of 105 feet (32 meters).

Once you reach the top, you will come to a platform. The overlook is small and there is really only one place with unobstructed views. Trees frame and block a lot of the view, but there is one spot where it is perfect.

So make a beeline to the center of the platform to take photos of the rainbow colors of the Grand Prismatic Spring. You can capture the entire hot spring with a wide-angle camera lens, or with your iPhone. Plus, you can get that perfect selfie.

People will be waiting in line, so don’t spend too long. We just kept going in and out as people left. Surprisingly, a lot of people came up for one quick snap and moved on.

Fairy Falls

If you have time, you may want to hike out to Fairy Falls, it is the tallest front country waterfall in Yellowstone at 220 feet high (67 meters). From the overlook, you can continue along the trail to the right to rejoin the Fairy Falls Trail.

The out-and-back trail is a 5-mile trip that takes 3 hours so if you have a few days in Yellowstone I say go for it! And if you are really keen continue on for another 15 minutes or so and come up on the Imperial Geyser and Spray Geyser. Read more about hikes in Yellowstone: 12 Best Hikes in Yellowstone National Park

Staying Safe at Grand Prismatic Spring

Note: If you are hiking in Yellowstone, walk in pairs and make plenty of noise to let wildlife know you are approaching. The park recommends carrying bear spray and there are places around the park that rent it.

Never go off the path, boardwalk, or trails at Grand Prismatic Spring. Not only is it dangerous, but it is also illegal and the environment is fragile. The boardwalks are there for a reason, to protect you and the environment. So stick to the paths.

It can be very windy at Grand Prismatic Spring, so hold on to your loose articles such as hats. We saw a hat floating in the waters of Mammoth hot springs. Foreign objects that fall into the pools have really hurt the geothermal features around the park. When the vents become clogged, the heated water cools killing the organisms.

Can you Swim in Grand Prismatic Spring?

The hot springs of Yellowstone are not for swimming, including Grand Prismatic Spring. You cannot swim in Grand Prismatic. There are only two designated swimming areas in the national park, Boiling River, and Firehole River Swim Areas. It can be dangerous to swim in Yellowstone Lake and its rivers due to cold temperatures. However, with boiling water and hot springs scattered throughout the park, you can also run the risk of scalding. It is forbidden to swim in geothermal areas.

How to Get to Grand Prismatic Spring

We flew into Cody Wyoming and feel that it is a fantastic place to start your road trip. Cody, Wyoming is located 50 miles from the East Entrance and is a place that you should spend at least two days exploring. And the closest entrance to Grand Prismatic Spring is through West Yellowstone is only a 30-minute drive.

Upper Geyser Basin

Once you are finished at Grand Prismatic, make your way to Upper Geyser Basin to see Old Faithful. It’s just a short distance from Midway Geyser Basin (15 minutes up the road) and the two Yellowstone attractions are perfect to visit together.

Plus, I would wait to use the toilets in the Old Faithful area. There are toilets at Midway Geyser Basin, but the hotels and ammenities around Old Faithful are better and see fewer people.

In Conclusion

Oh Yellowstone, you really need weeks to explore its beauty. Grand Prismatic alone can take a couple of hours to see. Add in the hike to Fairy Falls and you have an entire half-day booked in Yellowstone National Park. With Grand Prismatic Spring you have seen the most spectacular spring of rainbow colors in the park, but there is still so much more to see and do.

And there you have it, now that you know some of the facts, you are ready to visit Grand Prismatic Spring? This really was an amazing site to see. We had seen pictures online but really could not comprehend the beauty of Grand Prismatic and all of Yellowstone’s hot springs until we saw them with our own eyes. If you are looking for amazing places in the world to add to your bucket list, Grand Prismatic Spring is a must-visit destination.