Hot Springs in Yellowstone National Park

Yellowstone National Park is famous for its hot springs, which are geothermal features formed by heated groundwater rising to the surface. These hot springs come in various sizes and colors and are a testament to the park's geothermal activity. 

The park boasts thousands of hot springs with vibrant colors caused by different types of heat-loving microorganisms known as thermophiles.

(1) Grand Prismatic Spring

Grand Prismatic Spring is one of the most iconic and visually stunning hot springs in the park. It is 200-330 feet in diameter and more than 121 feet deep.

It's located in the Midway Geyser Basin and is known for its vibrant colors, which are created by thermophilic bacteria that thrive in the hot water. The center of the spring is a deep blue, surrounded by rings of yellow, orange, and red.

Grand Prismatic Spring is the largest hot spring in the United States, and the third largest in the world, after Frying Pan Lake in New Zealand and Boiling Lake in Dominica. 

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

Grand Prismatic Spring

(2) Mammoth Hot Springs

Mammoth Hot Springs is a fascinating geothermal area in Yellowstone National Park, known for its striking terraces formed by the deposition of calcium carbonate. The hot springs are situated in the northern part of the park, near the park's headquarters at Mammoth Hot Springs. This area is notable for its unique landscape of terraces, which have been created over thousands of years by the flow of hot, mineral-rich water from underground springs.

The terraces vary in color from white and tan to bright orange and green, depending on the types of bacteria and algae that thrive in the water. The formations are constantly changing as the geothermal activity shifts and new mineral deposits are formed. The Mammoth Hot Springs area is also home to a variety of wildlife, including elk, which are often seen grazing in the meadows around the springs.

Visitors can explore the terraces via a series of boardwalks and trails that provide close-up views of the formations. The historic Mammoth Hot Springs Hotel, built in 1937, is a popular spot for accommodations and dining. The area has a rich history, with archaeological evidence showing that Native American tribes, such as the Shoshone, have visited the hot springs for thousands of years.

The combination of geological wonders and historical significance makes Mammoth Hot Springs a must-see destination for visitors to Yellowstone.

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

Mammoth Hot Springs

(3) Emerald Pool

Emerald Pool, located in Black Sand Basin, is a notable geothermal feature known for its large steaming pool surrounded by thin, solidified sinter. Historically, the pool exhibited a striking blue color, primarily due to the presence of yellow thermophiles which gave it a greenish hue. However, a recent decrease in water temperatures has caused significant changes in its appearance. The once-vibrant blue waters have given way to murkier, orange pools, influenced by the rise of orange thermophiles in the outwash channel.

The pool maintains an average temperature of about 136.3°F (58°C) and a pH of 9, indicating a mildly alkaline environment. Its average conductivity is measured at 2216 µS/cm, reflecting the concentration of dissolved salts in the water. The changes in Emerald Pool's appearance and thermal characteristics are consistent with the broader fluctuations seen in other geothermal features within Black Sand Basin.

Emerald Pool

(4) Crested Pool

Crested Pool, located in the Upper Geyser Basin of Yellowstone National Park, is a prominent hot spring renowned for its striking features. With a depth of 42 feet (12.8 meters), this spring is named for the "crest" of sinter that encircles its edge. Although classified as a spring, Crested Pool exhibits geyser-like behavior, occasionally erupting with boiling water that can reach heights of up to 6 feet (2 meters).

The pool's average temperature is about 191.1°F (88.4°C), maintaining a near-constant boiling state. This extreme heat inhibits the growth of bacteria, contributing to the spring's exceptionally clear blue water. The boiling action is particularly vigorous around the intricate sinter formations along the crest, creating a distinctive sizzling sound.

Crested Pool has an average pH of 8.9, indicating a mildly alkaline environment, and an average conductivity of 2269 µS/cm, reflecting the concentration of dissolved salts in the water. The combination of these factors contributes to its unique and dynamic geothermal activity.

Crested Pool

Crested Pool

(5) Morning Glory Pool

Morning Glory Pool is a distinctive hot spring located in the Upper Geyser Basin of Yellowstone National Park. It is named for its resemblance to the morning glory flower due to its vibrant colors and shape.

Historically a popular attraction, the pool has suffered from vandalism over the years, with visitors throwing coins, trash, and other debris into it. This damage has hindered the pool's water circulation and increased its cooling, allowing bacteria to flourish and affect its vibrant colors. Cooler temperatures allow orange- and yellow-colored bacteria to thrive.

The pool's average temperature is around 159.3°F (70.7°C), with a pH of 7.6 and a conductivity of 2098 µS/cm. While vandalism has lessened, it remains a concern, and visitors are encouraged to report any such activities to park rangers to help preserve the natural beauty of the spring.

Morning Glory

(6) Sapphire Pool

Sapphire Pool is a stunning geothermal feature in Yellowstone National Park, characterized by its large, clear blue water and solid sinter rim that is level with the ground. The pool’s edges are adorned with shallow sinter shelves that host vibrant yellow and orange thermophiles, adding to its visual appeal. 

Before the 1959 earthquake, Sapphire Pool was known for its geysering activity. However, the earthquake significantly altered its behavior. The pool was filled with muddied water, and its eruptions grew larger. It wasn’t until 1971 that the pool's water cleared up, though the geysering activity ceased and has not resumed since. The pool's last eruption occurred in 1991, suggesting a significant change in its plumbing system due to the 1959 earthquake.

The pool maintains an average temperature of 159.8°F (71°C), with a pH of 7.9 and a conductivity of 2239 µS/cm. These characteristics make Sapphire Pool a notable feature among Yellowstone's geothermal wonders.

Sapphire Pool

(7) Silex Spring

Silex Spring is a prominent hot spring located in the lower Geyser Basin of Yellowstone National Park. It is known for its distinctive appearance and geothermal activity. 

Silex Spring is an intriguing geothermal feature, named for the significant amount of silica it contains. The name "Silex" comes from Latin, meaning "silica," which reflects the high silica content derived from the surrounding volcanic rocks. These rocks release silica into the hot spring waters, leading to the formation of sinter. This sinter deposits line the pool and create terraces along the runoff channels.

The runoff channels, which are large and follow the boardwalk from the parking lot, are shaped by the flow from Silex Spring. The hot waters of the spring support a variety of thermophiles, microorganisms that thrive in extreme temperatures, contributing to the spring’s colorful and textured appearance. 

Silex Spring has an average temperature of 174.7°F (79.3°C), a pH of 8.4, and a conductivity of 2000 µS/cm. It last erupted in 2006, adding to the spring's dynamic nature.

Silex Spring

(8) Firehole Spring

Firehole Spring is a notable hot spring located in the Lower Geyser Basin of Yellowstone National Park. It is situated near the Firehole River and is part of the diverse geothermal landscape in this area.

The spring is known for its vivid blue color and its clear, hot water. The vibrant hue is the result of the interaction between the thermal water and the minerals it contains, as well as the specific microorganisms that thrive in such environments. The spring's color and clarity are enhanced by the fact that it has relatively low sediment compared to some other geothermal features.

Firehole Spring

(9) Canary Spring

Canary Spring is a fascinating hot spring located in the Mammoth Hot Springs area of Yellowstone National Park. It is renowned for its bright, colorful terraces, which resemble the appearance of canary feathers, giving the spring its distinctive name.

The spring is part of the Mammoth Hot Springs' extensive network of terraces, which are created by the deposition of calcium carbonate. As the hot water from the spring flows over the terraces, it deposits minerals, forming the striking white and yellowish formations that characterize Canary Spring. The terraces have a layered appearance, with some sections showing intricate patterns and colors that range from white to pale yellow.

Canary Spring, like other features in the Mammoth Hot Springs area, is constantly changing due to the shifting flow of geothermal waters and mineral deposition. The terraces in this area are a result of the geothermal activity that has been ongoing for thousands of years, creating a dynamic and ever-evolving landscape.

Visitors can view Canary Spring and the surrounding terraces via boardwalks and trails that provide access to the geothermal features while protecting the delicate environment. The vibrant colors and unique formations make Canary Spring a notable and scenic highlight in the Mammoth Hot Springs area.

Canary Spring

(10) New Trail Spring

New Trail Spring is located in the Norris Geyser Basin of Yellowstone National Park. It is a notable geothermal feature known for its distinctive appearance and activity.

The spring is characterized by its unique mineral deposits and coloration. Like many other hot springs in Yellowstone, New Trail Spring exhibits vibrant hues due to the presence of thermophiles—microorganisms that thrive in hot, mineral-rich waters. The colors and formations around the spring can vary depending on the temperature and mineral content.

Visitors can access New Trail Spring and other features in the Norris Geyser Basin via boardwalks and trails that allow for safe viewing while protecting the delicate geothermal environment.

New Trail Spring

(11) Palette Spring

Palette Spring is a vibrant and visually striking hot spring located in the Mammoth Hot Springs area of Yellowstone National Park. It is renowned for its vivid array of colors, which resemble a painter's palette, hence its name.

The spring's vibrant colors are the result of the various thermophiles (heat-loving microorganisms) that thrive in its hot, mineral-rich waters. These microorganisms create a spectrum of colors ranging from yellow and orange to green and blue, depending on their temperature preferences and the mineral composition of the spring. The colors are further enhanced by the minerals deposited around the spring, which contribute to its artistic appearance.

Palette Spring

Palette Spring

(12) Orange Spring Mound

Orange Mound Spring is a striking feature within Yellowstone National Park’s Mammoth Hot Springs area. Its name is derived from the dark orange hue, which is a result of orange cyanobacteria thriving on the travertine rock. This spring is distinctive for its elevated structure compared to the relatively flat terraces of the Mammoth Hot Springs. 

Unlike many other hot springs in Yellowstone, Orange Mound Spring is cooler, with a temperature around 170˚F. This cooler temperature supports the growth of the orange-tinted cyanobacteria, giving the spring its characteristic color, which can vary depending on nutrient availability throughout the year. 

The spring is considered quite old due to its shape and the minimal flow of water, which has allowed it to form cone-shaped features and contribute to the surrounding travertine deposits. The flow of Orange Mound Spring can be irregular, with periods of little to no flow followed by times of increased activity. This dynamic nature is part of what makes the spring fascinating to visit.

Visitors can view Orange Spring Mound and the surrounding geothermal features via boardwalks and trails, which provide access while protecting the delicate environment. The mound's striking color and the intricate patterns of mineral deposits make it a notable and visually impressive feature in Yellowstone.

Orange Spring Mound

(13) Black Opal Pool

Black Opal Pool is a striking feature in the Midway Geyser Basin of Yellowstone National Park. It is a large, murky blue pool surrounded by soft sinter and sparse vegetation. The pool's edges are marked by dark thermophile materials, and the outflow creates braided channels of orange and green thermophiles as it flows down a slight hill. 

The pool maintains an average temperature of around 98.2°F (36.8°C), with an average pH of 8.7 and an average conductivity of 2089 µS/cm. Although it is primarily known as a hot spring with a typical temperature of approximately 132°F (56°C), Opal Pool is classified as a fountain-type geyser.

Black Opal Pool was created by a series of steam explosions in 1934, with additional smaller explosive events taking place in 2005 and 2006.

Opal Pool

(14) Rainbow Pool

Rainbow Pool is a fascinating feature of Yellowstone National Park. With its 100-foot (30.5-m) diameter, it’s a striking sight with its clear blue water surrounded by vibrant orange thermophiles. The pool's eruptions are rare, the last recorded one being in 1996. Its overflow runs down the sinter shelf, eventually reaching the Firehole River.

The pool maintains an average temperature of 149.3°F (65.2°C) and has a highly acidic pH of 3.5, which contributes to its unique coloration. The conductivity of 2306 µS/cm indicates a high level of dissolved minerals in the water. The combination of these elements creates a visually stunning and geologically significant feature in the park.

Rainbow Pool