Spanning a diameter of 370 feet and reaching depths of 121 feet, the Grand Prismatic Springs is both longer than a football field and deeper than a 10-story building. In fact, the colossal spring is the third largest hot spring in the world and only is smaller in size than New Zealand’s Frying Pan Lake and the Boiling Lake in Dominica.
And while Old Faithful may be Yellowstone National Park‘s most famous geothermal attraction, the Grand Prismatic Spring is the true gem of the extensive preserve. Located in the Midway Geyser Basin, the Grand Prismatic Spring is one of the most unique attractions in the country and is a must-visit landmark when trekking Yellowstone.
Despite the water’s elevated temperatures and potentially acidic composition making the spring unsuitable for swimming, the pure size and vibrant coloration of the site make the Grand Prismatic Springs one of the most majestic geothermal features in the world, and millions of visitors from around the planet flock each year to gawk at its rainbow waters.
From the best viewpoints to observe the phenomenon to the top nearby attractions and accommodation options, this is everything you need to know before visiting the Grand Prismatic Spring, Wyoming.
History of Grand Prismatic Spring
When early European explorers passed through the area that is now the Midway Geyser Basin, they returned home with stories of a colorful spring. Later, in 1839, fur trappers passing through the region again observed a phenomenon they referenced as a boiling lake.
While it’s unknown for sure, both of these references are believed to chronicle the Grand Prismatic Springs’ earliest interactions with the Euro-American world. However, despite these earliest visitations, the discovery of the colossal spring is attributed to the Hayden Expedition, which officially named the landmark in 1871.
While Ferdinand Hayden wrote about many attractions within the Yellowstone region, none were as detailed or beautiful as the Grand Prismatic Springs. In his report, Hayden wrote about the springs’ incomparable “vividness and delicacy of color” and even claimed that human art couldn’t even start to reflect the site.
Hayden’s recounting of the hot spring was so idyllic and detailed that Yellowstone National Park was officially established only six months after the Grand Prismatic Spring’s discovery to preserve the iconic landmark and the similarly beautiful attractions surrounding it.
Grand Prismatic Spring Facilities
Protected within Yellowstone National Park, the Grand Prismatic Spring continues to exist within the same primitive state it has enjoyed for thousands of years. The only exception to this lack of any development is the presence of a boardwalk that visitors must confine their visit to ensure safe and regulated viewing of the natural attraction.
Unfortunately, this also means visitors cannot submerge in the Grand Prismatic Spring’s mineral waters. But considering the scorching 189-degree Fahrenheit temperatures and the acidic composition of the waters, this is probably for the best.
Luckily, the colossal size and vibrant rainbow colors that provide the spring its name are marvels within themselves and provide a surreal spectacle by mere observation alone. From the boardwalk, visitors from around the world watch the natural process of the spring as the water shifts and changes color in breathtaking fashions.
Unlike geysers, which erupt thanks to an obstruction near the water’s surface causing power build-up, geothermal springs are open bodies that allow water to rise as it heats and fall as it cools. In the Grand Prismatic Spring, spectators watch as the boiling water in the center rises from its 121-foot depths before spreading across the surface as it cools.
Meanwhile, the distinct color spectrum that the springs display is directly related to the pool’s cooling process. Thanks to the presence of thermophile (heat-loving) bacteria that thrive in the springs, the waters change color depending on the variety of bacteria that can exist at different temperatures.
The effect of these bacteria and the varying spring temperatures is one of the most picturesque natural phenomena in the world. It makes a visit to the Grand Prismatic Spring worth the journey despite being unable to swim in its waters.
Attractions Near the Grand Prismatic Spring
While Yellowstone National Park is filled with numerous wondrous attractions scattered throughout its protected area, the region surrounding the Grand Prismatic Spring boasts the greatest concentration of geothermal marvels.
Old Faithful
No trip to Yellowstone National Park would be complete without visiting the famous Old Faithful Geyser. Luckily, the renowned geyser is located only 7.4 miles south of Grand Prismatic Spring and is an easy addition to an itinerary when visiting the thermal pool.
The most famous geothermal attraction in the national park, Old Faithful, has garnered its name thanks to its reputation as a unique geyser whose eruptions are predictable with a fair bit of accuracy.
This is because the geyser erupts approximately 20 times daily, resulting in an average discharge of nearly once every hour.
Excelsior Geyser Crater
Also located within the Midway Geyser Basin, the Excelsior Geyser Crater is only steps from the Grand Prismatic Spring and is observable from the same boardwalk it shares with the thermal pool.
While once active at the time of its discovery during the same Hayden Expedition that uncovered the hot springs, the geyser has since become dormant.
However, while the site may no longer experience eruptions, the pool it created continues to discharge up to 4,500 gallons of scorching 199-degree Fahrenheit water per minute into the Firehole River.
Accommodations Options at Grand Prismatic Spring, Wyoming

Located in one of the most popular regions of Yellowstone National Park, the Grand Prismatic Springs features several nearby accommodation options both within the national park and in the nearby West Yellowstone.
The easiest way to spend the night in Yellowstone National Park is by pitching a tent in one of the preservation’s many campgrounds. The nearest campsites to the Grand Prismatic Spring are within the Madison Campgrounds, only 10 miles to the spring’s north.
Alternatively, visitors seeking a more historical and comfortable night stay in Yellowstone’s geothermal region may prefer to stay at the Old Faithful Inn. This cozy lodge option features 300 rooms, two restaurants, a bar & lounge, and a snack bar.
Unfortunately, the hotel is often fully booked, and visitors may need to reserve their room a year in advance.
Getting to the Grand Prismatic Spring, Wyoming
The easiest access point to enter Yellowstone National Park to visit the Grand Prismatic Spring is through the West Yellowstone entrance.
Upon entering the park, visitors headed to the springs should follow the US-191 for 14 miles until they come to Madison Junction. At the intersection, continue along the US-191 to the south for another 10.1 miles before arriving at the spring’s parking lot.
Details
- Address: Yellowstone National Park, WY 82190, United States
- Phone: +1 307 344 7381
- GPS Coordinates: 44.52513, -110.83823