The Stillwater River offers excellent flyfishing opportunities. The Stillwater River begins in the mountains of the Absaroka-Beartooth Wilderness Area where it runs for 20 miles. Upon leaving the wilderness area, the Stillwater River continues another 45 miles through canyon, forest and prairies on the way to the confluence with the Yellowstone River close to Columbus. This rocky river is very popular with the locals since the other main rivers are packed with tourists. The most desirable section is that in the wilderness area which requires horseback riding or hiking. From the headwaters to the town of Nye, the whitewater current is swift and the trout seek out pockets. The trout tend to be small, around 8 to 10 inches. There are rainbow trout, cutthroat trout and brook trout.
Overall, Stillwater River is the 14th most popular fly fishing river of all 21 fly fishing spots in Montana.