Midway Geyser Basin - Up Close With Grand Prismatic

Photo: Steven Pavlov, CC BY-SA 4.0 (cropped)

A stop on Yellowstone Geyser Country, a free self-guided tour.

Cross the footbridge over the Firehole River and you'll see streams of steaming water pouring off the bank above you. That's runoff from Excelsior Geyser Crater, a huge boiling pit that sends roughly 4,000 gallons of hot water into the river every minute.

Excelsior was once a giant. In the 1880s it threw water as high as 300 feet, by one park superintendent's account, then went mostly quiet. In 1985 it woke up for about two days, with most eruptions reaching around 30 feet.

Farther along the boardwalk, Grand Prismatic Spring spreads out at your feet. Down here you see the delicate orange channels its runoff carves into the crust, and on cool days the steam itself glows blue and orange from the colors below.

Hold on to hats and keep kids close: wind gusts across this flat, and anything that blows onto the crust is lost for good. Never step off the boardwalk; the water here can cause severe burns.

Getting here: Drive a mile north from the Fairy Falls Trailhead to the Midway Geyser Basin lot on the left, then walk across the footbridge over the river.

Did you know?: Grand Prismatic is the largest hot spring in the United States and the third largest in the world.

Photo op: Where the boardwalk passes the spring's edge, crouch and shoot low across the orange runoff channels; on cold mornings, the colored steam is the picture.

Nearby: Vault toilets at the parking lot; no food or water. The lot fills fast at midday, so be patient and park only in marked spaces.

More on Wikipedia: Excelsior Geyser · Grand Prismatic Spring · Geothermal areas of Yellowstone

Midway Geyser Basin - Up Close With Grand Prismatic

Stops on this tour