Gallatin River

The Gallatin River carves through one of Montana's most beautiful canyons, a stretch of pocket water, plunge pools, and cascading riffles that demands precise casting and rewards it with wild trout.

Originating in Yellowstone National Park near the northwest corner, the Gallatin flows north through a forested canyon bordered by Highway 191. This canyon section between Big Sky and the mouth near Gallatin Gateway is the heart of the fishery — roughly 30 miles of accessible, wadeable water holding both rainbow and brown trout.

The Gallatin is not a river of large fish. Most trout run 10 to 14 inches, with occasional fish to 18 inches. What it lacks in trophy potential, it makes up for in sheer numbers and willingness. On a good summer day, a skilled angler can expect to catch 30 to 50 fish on attractor dry flies and small nymphs.

The canyon's character makes the Gallatin excellent for beginner and intermediate anglers. The fish are aggressive and forgiving of imperfect drifts. High-floating attractor patterns like Royal Wulffs, stimulators, and Chubby Chernobyls work throughout the summer. Fall brings spawning browns from the lower river into the canyon.

Below the canyon, the Gallatin enters an agricultural valley before joining the Madison and Jefferson at Three Forks. This lower section fishes differently — slower, deeper, with larger brown trout but less consistent action.