The Most Fantastic Grand Prismatic Spring, at Yellowstone National Park

Deposit pattern of the Grand Prismatic Spring

 

 

Date: July 20, 2020 and September 30, 2024

Place: Yellowstone National Park, Wyoming

Coordinates of the Fairy Falls parking lot:  44.515649, -110.832490

Coordinates of the Midway Geyser Basin Trailhead: 44.528455, -110.836239

Level: easy

 

Together with the Old Faithful geyser and the bison, the Grand Prismatic Spring is the poster feature of Yellowstone National Park. Of course we couldn't miss it! As it happened, the Grand Prismatic Spring was the last feature we visited on both my 2020 summer trip with the youth, and the 2023 fall trip with my sister. Our trails and observation points were however, different. On my July of 2020 trip with my chikas and their friends we took the upper view trail, starting at the Fairy Falls parking lot and going northward west of the Midway Basin, where the Grand Prismatic Spring was. 

 

July 2020

Already at the parking lot we had some excitement, when we saw that the best parking spot was already occupied - by a bull bison. The bison merely stood there calmly, in total disregard of the numerous people walking by, not to mention the constant vehicular traffic there. Thankfully, no human there approached the beast or tried to provoke it in any way.

Bison Parking

The first thermal pool we saw on that hike was the River Geyser, which was right by the parking lot. The pool's water was clear turquoise, hemmed with microbial orange. It was a beautiful preview of the Grand Prismatic Spring.

River Geyser

Shortly after we crossed the Firehole River on a low bridge. The Firehole River is the same one that collects basin thermal water from the west side of the Yellowstone Caldera, including the Old Faithful Basin drainage. One might think that the river water would be hot, or at least warm, but it was in fact, quite cold.  

Firehole River, view south

The trail continued along the river on its west side. More geyser pools were present on our way, between the trail and the Firehole River. None of the geyser erupted while we were there. Their pools looked very calm and serene. 

Catfish Geyser

There were some wildflowers along the path as well, though not as many as I've seen on other trails we've hiked in Yellowstone at on that trip. 

A rusty color spot on the ground indicated eitherthe deposit of minerals r more likely, the flourishing of certain microorganisms. 

The rusty soil stain was being fed by a nearby small geyser, the Flood Geyser. I don't remember if there was a sign there explaining the name. I can only assume that the geyser pool occasionally overflows and floods the vicinity. 

Flood Geyser

 I noticed some more wildflowers along the trail and I paused for a closer look, letting the youth get ahead of me. 

Paintbrush, Castilleja sp.

For the most part, on the west side of the trail was a hill's slope. In one place however, the hills retreated a bit and in the flat area between the slope and the trail was a lovely, green meadow. I scanned the meadow for wildlife but didn't see any other than insects. 

When I caught up with the youth they were already looking over the Grand Prismatic Spring, along with numerous other visitors who hiked this trail for the same purpose. I joined them and looked with awe at the magnificent sight that spread below us. 

Grand Prismatic Spring

The Grand Prismatic Spring is the largest thermal pool within Yellowstone National Park. Taking a closeup look at the pool's edge it is easy to see how it got its name - the lines of color looked like they were coming through a prism. The pool's water was hot, so the signs say, but no steam was obstructing our view. The Grand Prismatic Spring was indeed grand, and it was absolutely marvelous! 

Another thing I noticed was a boardwalk loop trail that allowed visitors to get really close to the spring, and I regretted not having enough time to go on that one as well.

We looked at the pool for a long time, and took many photos, making it a tough choice for me later which of them to post here. Eventually though, it was time to go. 

Trail

I assume that because of the pandemic there were fewer visitors there than there would have been otherwise. Still, all the human activity on the trail did raise a lot of dust into the air. The dust settled on the nearby vegetation, coating the leaves, dulling their natural gloss. 

Thimbleberry, Rubus parviflorus

We crossed the Firehole River again on our way back. A large, orange dragonfly stood poised on the rail, undisturbed by the people walking back and forth on the path.

Dragonfly

Near the parking area I turned and looked back on the Firehole River. After this walk we would drive out of Yellowstone National park exiting it to the east on our way to Thermopolis, Wyoming, where I promised the youth hot springs they could actually enjoy dipping in.

Firehole River

September 2023

Yellowstone National Park is one of the most impressive and magnificent places I've ever been to, and the Grand Prismatic Spring is one of the signature geothermal features within the park. Naturally, when I visited Yellowstone with my sister last fall, the Grand Prismatic Spring was on out list of places to see. We didn't walk the same trail as I did with the youth in 2020 though. Instead, we took the boardwalk loop that was right inside the Midway Basin, allowing visitors to approach the thermal pools. 

No bison was waiting for us at the parking area this time. There were some wildflowers, though.

Cinquefoil, Potentilla sp. 

As soon as we left the parking area we crossed the Firehole River and a low, flat bridge with nice, sturdy rails we could lean on and look onto the river. Across the river. steaming hot water was flowing down the bank slope, merging with the cold river water.

Firehole River

From a distance we couldn't actually see the flow of the hot water because it was masked by the steam. Up closer on the west side of the bridge we had a much better view of the thermal water collecting from that part of the basin.

The rust-colored lines and spots turned out to be mats of thermophilic microorganisms. These, and many other species of thermophile life is what gives the wonderful colors to the edges of the Grand Prismatic Spring and of the other geothermal springs there.

We moved towards the next geothermal feature - the Excelsior Geyser. At least, that's what the posted sign said. We could barely see the edges of the pool because the steam emanating from it was so thick. We could see it was very colorful though, certainly on the edges. 

Excelsior Geyser

The water of the geyser pool was brilliant turquoise, and it was very, very clear. The sign by the geyser said that it had only very few, and very violent eruptions during recorded history, the last one being in 1987. It didn't erupt while we were there. 

Excelsior Geyser

The entire trail was a boardwalk, of course, to keep both people and the unique landscape safe. I gazed on the basin area, the flat, almost barren of any higher plants, and the steaming fumaroles. It did look outlandish. 

Slowly we were approaching the Grand Prismatic Spring. I could already see that we won't get to see much of the pool itself, if any. The steam rising from it was simply too dense. It did however, Make the perfect background for the visitors walking on the boardwalk near the pool's edge. 

The travertine pattern created by the mineral deposits of the Gran Prismatic Spring was spectacular. Like little flooded terraces, farmed with minute thermophile microorganisms. It looked sleek, beautiful and eerie at the same time. 

The smooth flooded microterraces made a perfect reflective surface. had it not been for the hot steam that warmed up the rather chilly air I could have thought that the surface was made of polished ice. 

Soon we were walking right by the edge of the Grand Prismatic Spring. I was right about not being able to see the pool itself - the steam was too thick. But we were walking right by the microorganisms - rendered color lines that belted the pool and gave it its wonderful prismatic colors. 

Like rays extending from the sun the streaks of orange, beige and brown stretched away from the pool's edge. I was wondering what where hikers on the higher trail seeing now. I thought that they might not see much better than us because of the steam. We got to see the pool edge patterns up close, and they were stunning. 

I couldn't help myself. I just had to post one more close up photo of this magnificent color pattern. Even so, the photos hardly do justice to the actual thing. To get the full grandeur of the Grand Prismatic Spring, one has to be there in person.  

As we slowly made our way away from the Grand Prismatic Spring we approached a couple of other thermal pools. One of these, the turquoise Pool was this almost perfect round funnel. Like the Excelsior Geyer, it too had very clear water. We could see the pool well though. The steam coming from it was thin and didn't mask our view. 

Turquoise Pool

I looked down the slope beyond the pool where the thermal water seeped and collected into little brooks that flowed into the Firehole River. On the horizon behind the green forest on the east side of the river rose to high peaks. I haven't figured out which mountains these were. Perhaps the large one was Mount Washburn. 

We completed the loop near the Excelsior Geyser again. The steam seemed ever so thinner and we got to see some f the other colors that adorned the geyser's edge. 

On the bridge I paused again to look at Firehole River. Nothing in the deep blue flow suggested that this river collected thermal water from geyser basins throughout its length.

Firehole River, View north

As I looked at the river an osprey made a dive into the water. It wasn't successful that time but I kept watching the magnificent raptor for a while as it was flying back and forth over the river, searching for fish. 

Osprey

The osprey try a couple more times but was not successful in any of them. Eventually I wished him luck and my sister and I completed crossing the bridge, not before I took one more goodbye shot at the Firehole River where the thermal water steamed down the slope from the basin where it had emerged from the depths.   

Firehole River, View South

The Grand Prismatic Spring was our last stop in Yellowstone National Park on both my 2020 trip with the youth and my 2023 trip with my sister. Neither trip was over though. After Yellowstone, my sister and I took the long way route back home - a route that went through Southeast Oregon, Northern Nevada, and Northern California. It was a great trip and we did see many more interesting things but we didn't do any more hikes. On my 2020 trip with my chikas and their friends however, we took and even longer route - through Thermopolis, Fort Washaki, and eventually Dinosaur National Monument on the Utah/Colorado border, where we did hike a couple more trails that I would post about later down the line. The Yellkowstone chapter of this blog however, is now done, all written and posted. I don't know when next I would visit this outstanding place, but I sure hope to be there again. 

More Appealing than its Name: The Mud Volcano Exploration Walk in Yellowstone

September 2023

Date: July 20, 2020 and September 30, 2023

Place: Yellowstone National Park, Wyoming

Coordinates: 44.624691, -110.433234

Length: 1 mile

Level: easy

 

The last day in Yellowstone on both my 2020 and my 2023 trips involved visiting the same three places - The Yellowstone Falls, The Mud Volcano, and the Grand Prismatic Spring. On our 202o trip that day started with decamping and getting ready for the day's trip. During the morning preparations my elder chika encountered a lifer bird in the grass - a pine grosbeak, and her excitement soared to the sky. After breaking camp we went to theYellowstone River Rim Drive, where we took a short walk to Artist's Point to observe the Lower Yellowstone Falls. 

Pine Grosbeak

Driving south from Yellowstone Falls, the next obvious stop would be the Mud Volcano. The Mud Volcano is a relatively small basin but a very interesting one. On both my recent trips to Yellowstone, the July 2020 road trip with the youth and the September 2023 road trip with my sister we stopped at the Mud Volcano for some exploration. I describe both hikes here as they are fairly short. 

Mud Volcano Basin

There is a small loop boardwalk that surrounds the main basin area. There is also a larger loop trail higher on the hillside, leading to a few larger thermal pools. On my 2020 visit we hiked both trails, starting with the larger one. 

Our hike as captured by my GPS

We started our hike going west. Alkali vegetation grew right by the geothermal features but a bit higher up more ordinary plants were thriving, and some were blooming too. Wildflowers were blooming here and there within the grass and rushes.

Lupine, Lupinus sp.

The wildflowers at the Mud Volcano Basin weren't as numerous or as spectacular as I've seen on previous hikes in the area, but I didn't mind that. It only meant I didn't stop as frequently and I could keep pace with the rest of my party.

Many butterflies flew around the wildflowers. They were very active and were difficult to focus on. Ocassionally one would pause somewhere for a little bit and I could take its photo.

Azure Butterfly

Higher up the boardwalk trail I took in the view of the the green valley we walked along. The day was as beautiful as it could be. The weather was perfect and the colors brilliant. The beautiful day didn't smell like roses though. The smell was more fitting of a geothermal area, imbued with sulfur odor whiffing in and out in light waves on the air. 

Soon enough we approached the higher features that sourced the sulfur odors. Large bubbling thermal pools greeted us at the upper arch of the boardwalk. 

Small trail spurs led us to observation decks, overlooking the pools. It was interesting to see how different they were one from another, even when cat a close distance. One had almost clear water, and the others were of pasty, bubbling mud. 

Some of these pools reminded me of the Sulfur Works geothermal area at Lassen Volcanic National Park. The sheer scale of the Yellowstone geothermal features however, was unsurpassed by anything else I've seen. 

The upper boardwalk loop was near a few other geothermal features. Some of the pools were clearly not hot, or at east not as hot - vegetation was growing right at the water. Little gas bubbles rose to the surface, giving the pool a soda-like appearance. Perhaps these were carbonate bubbles which would make this pool a true soda pool. 

Another mud pool seemed unmoving at all. It was covered with a  film of muck - likely microorganisms, either bacteria or micro algae.  

In between the pools there were more wildflowers blooming. Even the small and modest willowherb looked more festive blooming in the scenery of the volcanic basin. 

Willowherb

From the highest point of the trail we had a nice view, not only of the lower part of the basin but of the area beyond it - the blue strip of the Yellowstone River and the forest that belted it. 

Down below us was the largest mud pool of the Mud Volcano basin. Steam rose form the corner of the pool. A sign post said this was the Mud Geyser - a geyser that erupted only twice within recorded history. We watched it for some time but it didn't erupt for us, so we moved on. 

The boardwalk trail led us downhill toward the lower part of the basin. Things were abut to get a lot more exciting there, and not because of the geysers. Not knowing that however, I still enjoyed the calm day and the lovely wildflowers along the trail. 

Cinquefoil, Potentilla sp. 

We descended back to the lower area of the Mud Volcano basin right to the part called, "The Boiling Hillside". This area used to be forested but a series of earthquakes in the late 70's caused the rise of thermal water through the earth there, which killed the trees. the dead, fallen trees are strewn all over the place there, above the boiling pool. 

The Boiling hillside

That by itself was an interesting sight, but what made it more exciting was a large bison bull that lowed its way up that hillside, completely unconcerned with the possibility of sliding down into the boiling water below. 

We turned to walk the smaller, lower loop of the Mud Volcano. A dust-bathing bison, also male, was enjoying himself in the middle, in complete disregard of the numerous people observing him from the elevated trail.  

Another bull bison stood very close to the board walk. Human visitors grouped by the rail, trying to get the perfect shot of the massive beast. 

The bison soon delivered the goods - he too dropped into the sand and started rolling in it with clear excitement. The reason turned out to be that the bison from the other side was approaching. 

What followed next I didn't catch on camera - the two bull bisons got engaged in a pre-fight dominance show off that involved getting onto the boardwalk. All the humans that were there including myself and the youth in my group quickly retreated t a safe distance. By the time I got a clear view of the fight scene the loser was already retreating up the valley to the higher basin area. 

We didn't see any female bison herd nearby. The winner bull bison celebrated his victory by resuming his dust bathing activity. 

Calmness returned to the lower Mud Volcano basin. At least for the time being, only the thermal pools bubbled lively. People, including us, resumed our quiet stroll along the boardwalk. 

Lower Mud Volcano basin

We got to enjoy the Dragon Mouth geyser as the warm steam swirled around toward us, before returning to drift to the other side. 

Naturally, my eyes were attracted to the yellow spot on the other side of the pool, near the dragon's mouth - a large patch of yellow monkeyflowers. 

The lower, smaller boardwalk loop took us almost as long to walk as the upper, because of the bison excitements and also because this small area holds a lot of interesting features in it. I compare the photos I took then with photos I took of the same features three years later and find it fascinating to see what had changed and what stayed the same.

Lower Mud Volcano Basin

After completing the Mud Volcano Basin loop we found a place to have a picnic lunch and moved on to the Grand Prismatic Spring for our last Yellowstone hike for that trip.

Tiny Mud Spring

Three years later, on September of 2023 I was back in Yellowstone with my Sister. We had a shorter time there and didn't get to see all the places that I visited with my chikas and their friends in July of 2020. The lower Mud Volcano loop however, was one of the places we did visit and my sister found it as fascinating as I did.

Lower Mud Volcano Basin, September 2023

The bison were there on this visit as well. I guess they love this area. This time however, they did not provide any action. They weren't close to the boardwalk but remained up the hill. There were a couple of large bulls there, and behind them a herd of bison cows, well tucked in the trees. It was impossible to estimate how many bison were in that herd, and I couldn't get a clear photograph of the females hidden in the background.

Still, a bison is a bison. My sister, who has never seen one from our trip to Yellowstone, couldn't detach her gaze from these royal beasts. She did so eventually, to look at the geothermal features and to appreciate them with all of her senses, including smell and sans touch.

Mud Spring

As we walked around the larger pool in the middle of the boardwalk loop I noticed a clamp of cattails in one corner. I didn't recall seeing them there on the previous visit and when I checked my older photos I saw that indeed they weren't there at the time. Nature is in constant change. 

The water level in some of the areas was lower and the mud shaped itself into interesting and eye-pleasing patterns.

The steam emanating from the pool below the boiling hillside was much more visible. I thing that wasn't because there was more steam than in July of 2020 but because the air that day was considerably cooler, not to say cold even.

No bison were climbing the boiling hillside. I could see however, that the trees were making a comeback - there was a slow regeneration of the forest patch there. Perhaps the soil closer to the surface was cooling down.

 Revisiting any given place again can reveal that Nature is always in flux. In geothermal areas however, that change seems to happen faster and in more unexpected ways. I wonder how this place would look like on my next visit in Yellowstone. I hope it won't take me too long to go there again.