Grand Prismatic Spring
A vision of rainbow color and an otherworldly feel, it’s no surprise that the Grand Prismatic Spring is Yellowstone’s most photographed feature. It’s also the park's largest hot spring, measuring 370 feet in diameter and is over 121 feet deep.
Yellowstone’s Midway Geyser Basin may be small, but it packs a big punch: In addition to Grand Prismatic Spring, see Excelsior Geyser, an enormous geyser crater, Turquoise Pool, and Opal Pool.
The boardwalks make it easy for visitors to keep at a stroll’s pace while taking in all the sites. Follow the boardwalks across the Firehole River as it snakes through the thermal area.
Be sure to stay on the boardwalk. It is illegal and very dangerous to walk in the geyser basin.