The Clark Fork River is known for it wide range of trout including rainbow trout, brown trout, cutthroat trout and bull trout. The Clark Fork River starts at the confluence of Silver Bow Creek and Warm Springs Creek near the town of Anaconda. It flows generally northwest for 275 miles into Pend Oreille Lake. While most trout average about 15 inches, when fly fishing on the Clark Fork River you may find some large ones up to 20 inches long.
The upper Clark Fork River is the stretch from the headwater down to Milltown Dam. Some of the best fly fishing on the Clark Fork River is where several creeks enter the river: Rock Creek, Blackfoot River, and Little Blackfoot River. Access is provided by SR90.
Since it is closer to Missoula, the fly fishing section from Milltown Dam to Thompson Falls is popular with floaters. This is difficult water with few riffles or pockets, but there are nice rainbow trout to be found.
Overall, Clark Fork River is the 12th most popular fly fishing river of all 21 fly fishing spots in Montana.