Big Springs is one of the headwaters of the Henry's Fork of the Snake River. Crystal clear water wells up out of the ground here at a steady 52 degrees year round, which keeps the stream open and green even in winter.
From the bridge you can watch enormous rainbow trout holding in the current. They are protected here: there is no fishing at Big Springs. A short, accessible trail follows the water, with chances to see osprey, bald eagles, waterfowl and the occasional moose, and the historic Johnny Sack Cabin sits right beside the spring.
Big Springs is east of Mack's Inn, at the end of Big Springs Loop Road. A Forest Service campground is nearby. Winter access is limited by snow.
