The underrated Kootenai River loops south from British Columbia into extreme northwestern Montana, where the 17-mile tailwater below Libby Dam offers some of the state’s finest rainbow trout fishing. A 33-pound, state-record rainbow was taken by a spinfisherman below the dam here in 1997. Flyfishermen, meanwhile, will encounter abundant 12- to 16-inchers rising in the broad currents during July, with enough 18-inch-plus fish to warrant plenty of backing on your trout reel. Numerous small tributaries and area ponds offer exceptional fishing for smaller rainbows and westslope cutthroats. It’s possible to fish the big river from shore, but casting from a drift boat works best. More info: 406-293-3608;

Next Best: Yampa River, Colorado From Steamboat Springs in northwestern Colorado downstream through the Stagecoach Reservoir tailwater, the unsung Yampa River has big rainbows (and, in some areas, monster northern pike). More info: Fly Fishing Outfitters, 800-595-8090;