Idaho

A high-desert freestone under the Pioneer and White Knob ranges that turns, below Mackay Reservoir, into a short cold tailwater growing wild rainbows past 20 inches — then spreads out below Arco and sinks into the desert at the Big Lost Sinks without ever reaching the sea.

A hundred miles of roadless westslope cutthroat water running through the heart of the Frank Church–River of No Return Wilderness. Access is a five- to six-day float on a private lottery permit or an outfitted trip; the reward is eager dry-fly cutthroat protected as catch-and-release with single barbless hooks since 1973.

The Salmon is the longest undammed river in the lower 48 — 425 miles from headwaters at Sawtooth Valley to its confluence with the Snake near Lewiston. It runs through three distinct fisheries: roadside wild trout from Stanley to North Fork, the 'River of No Return' wilderness raft section, and a lower steelhead/smallmouth reach from Riggins to White Bird.

The Fall River is the largest tributary of the Henry's Fork, a runoff-fed freestone that tumbles off the Pitchstone Plateau in southwest Yellowstone, past a string of waterfalls, and out onto the potato ground east of Ashton. It fishes late — high and off-color into June, then a July salmonfly-to-PMD dry-fly river most Henry's Fork anglers drive right past.

The Henry's Fork is the spring-fed tailwater that runs from Henrys Lake through Island Park and on to its confluence with the South Fork Snake near Rexburg. The slow flat water of Harriman State Park (the Railroad Ranch) is the most famous technical dry-fly stretch in the West.

The South Fork is the 66-mile Palisades Dam tailwater that runs from the Wyoming-Idaho line through Swan Valley canyon to its confluence with the Henry's Fork near Menan. It holds native Yellowstone cutthroat alongside wild browns and rainbows at densities exceeding 5,000 fish per mile in the upper reach, and it's the West's best three-species native cutthroat fishery.

The Idaho Teton is a low-gradient, spring-influenced meadow river winding through Teton Valley between Victor and Driggs, with the Teton Range on the eastern skyline. It fishes like a big spring creek for native Yellowstone cutthroat that rise honestly to a good drift, then drops into a hazardous whitewater canyon that holds the biggest fish before spreading through farmland toward St. Anthony.

A big, cold, low-elevation river that draws anglers from all over for one thing: B-run steelhead — the largest summer-run steelhead south of the Canadian border, ocean-going rainbows that average 10-13 pounds and push past 20. It's classic spey country, swung flies on broad even-depthed runs from Lewiston up through Peck and Lenore, with a shoulder-season dry-fly window for native westslope cutthroat and rainbows when the main stem drops and cools.

A wild, unstocked freestone that runs right along US-12 for 70 miles of clear-water pocket water — native westslope cutthroat that eat dries two steps from the pullout, plus bull trout in the deep holes. Snowmelt-driven and treacherous to wade; it's a walk-and-wade river, not a trout float, and rarely comes into shape before mid-July.

A big, remote freestone above Dworshak Reservoir holding one of the Northwest's best wild westslope cutthroat fisheries — 79 roadless-feeling miles of pocket water and green runs where eager natives eat attractor dries. Its tributary Kelly Creek has been catch-and-release since 1970.

A remote wilderness freestone draining the heart of the Selway-Bitterroot, home to one of the most intact native westslope cutthroat populations left in America. The lowest 21 miles below Selway Falls are the only road-accessible, DIY water; everything above is a permit-only, lottery-drawn Class III-IV float. Snowmelt-driven with a short, sharp season — it rarely drops into shape before mid-to-late June, then fishes big dries through summer.

The Panhandle's dry-fly river — a snowmelt freestone running roughly 50 miles through cedar forest to Enaville, holding wild native westslope cutthroat that eat attractor dries all day from June through October. Catch-and-release on cutthroat river-wide; no bait and barbless above Yellow Dog Creek.

One of the best native westslope cutthroat dry-fly rivers in the Lower 48 — catch-and-release above Prospector Creek, a walk-and-wade freestone up top and floatable big water below Avery, where cutthroat eat attractor dries off the top once June runoff drops.

The freestone that runs down the spine of the Wood River Valley past Ketchum, Sun Valley, Hailey, and Bellevue — a wild, unstocked river of heavily spotted rainbows and thick lower-river browns, best fished on foot with a dry-dropper once July runoff clears.

Idaho's iconic spring creek near Picabo — glassy, weed-lined meadow flats holding wild rainbows and browns, protected in part by The Nature Conservancy's Silver Creek Preserve. Technical sight-fishing to selective risers with long leaders and small flies; famous for its Brown Drake and Trico hatches.

The rare trout tailwater you can fish on a lunch break — cold, clear water off the bottom of Lucky Peak Dam runs straight through downtown Boise, paralleled the whole way by the paved Greenbelt. Wild brown and rainbow trout (browns commonly 16-20 inches), native redband, and abundant mountain whitefish. Flood-control and irrigation releases dominate: summer often pushes 1,000-7,000+ CFS and fishes poorly, but the river turns on after irrigation season ends in fall and through winter at a wadeable 150-600 CFS.

The tailwater below Anderson Ranch Dam is the big-wild-trout river every Treasure Valley angler defaults to — cold, nutrient-rich water off the bottom of the reservoir holds 3,000-plus trout per mile and fishes twelve months a year. How it fishes depends entirely on the dam release: a wader's river under 600 cfs, a drift-boat river at summer irrigation flows near 1,600 cfs. Fly-fishing-only, mostly catch-and-release.