Grand Prismatic Spring is a vast hot spring in Midway Geyser Basin, Yellowstone National Park. Its blue centre is ringed with green, yellow and orange bands created by heat-loving microbes in the water. Walk the boardwalk for a close view of the pool and the surrounding geothermal features, including Excelsior Geyser Crater and Turquoise Pool. For the spring’s full circular shape, take the short hike to Grand Prismatic Overlook. The boardwalk loop takes about 30 minutes; allow about an hour for the overlook route.
Two ways to see the spring
Grand Prismatic Spring lies in Midway Geyser Basin and is more than 370 feet across. Its size is easier to take in from above, while the boardwalk brings you close to the water and the coloured edges. Combining both routes gives you two distinct views of the same geothermal feature.
The boardwalk loops around the spring and takes about 30 minutes. From it, you can see the blue centre and the bands of colour around the pool. The colours come from heat-loving microbes living in water at different temperatures. Nearby, Midway Geyser Basin also includes Excelsior Geyser Crater and Turquoise Pool.
The view from Grand Prismatic Overlook
The overlook trail provides a raised view of the spring’s full circular shape and its coloured rings. The route is described as a short hike, with a distance of about 0.8 miles one way in the supplied trail details. Allow about an hour for the overlook visit.
A sunny morning is suggested for seeing the colours from above. Cool mornings can bring rising mist, but heavy steam can make the spring harder to see clearly. The area can be busy, so an early start may help you avoid some of the crowds.
Stay on the boardwalks
The spring’s hot water and surrounding ground are fragile geothermal features. Keep to the boardwalks and do not step into the spring or onto the surrounding landscape. From the path, you can observe the pool at close range without disturbing the area.
FAQ
How long do you need at Grand Prismatic Spring?
Allow about 30 minutes for the boardwalk loop or about an hour for the overlook visit.
Can you see Grand Prismatic Spring from above?
Yes. The Grand Prismatic Overlook trail gives an elevated view of the spring’s full shape and coloured rings.
What causes the spring’s colours?
Heat-loving microbes living in water at different temperatures create the coloured bands around the pool.
When is a good time to visit the overlook?
A sunny morning is suggested for a clearer view of the colours. Cool mornings can bring mist, which may obscure the spring.
