Grand Prismatic Spring

The Grand Prismatic Spring is another of Yellowstone’s iconic hydrothermal features. It is the one that looks like a big orange and blue eye. The spring sits along the Firehole River in the general area of the Upper Geyser Basin where Old Faithful resides. It produces a constant flow of water that flows into and heats the Firehole River. To me, the Firehole River is the most fascinating of Yellowstone’s rivers. It flows from Madison Lake, on the continental divide, 21 miles to the Gibbon River at Madison Junction. What fascinates me, is that it travels through the Upper Geyser Basin, where Old Faithful is located, and past the Grand Prismatic Spring. Those and other hydrothermal features dump their water into the Firehole. This raises the temperature 9-18 degrees Fahrenheit.

The pool filled by the Grand Prismatic Spring is very shallow. It is colored by the brown. orange and yellow bacteria and algae that grow in its pool. The sun highlights its colored features and the water reflects the blue of the sky. Steam rising from the spring adds mystery to the landscape. Though you can appreciate the spring by just giving it a cursory walk-by, paying attention to the details and seeing how the light seems to make them change provides a breathtaking experience.

Here is a link to an image that shows the spring in totality:; I don’t have one of my own to share.

Note: Click on caption to see higher resolution image.

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