Big Smokey Hot Spring

What to expect

Big Smokey Hot Spring is one of the obscure entries on Idaho’s hot spring lists. Thermal spring inventories place it high on Big Smoky Creek in the Sawtooth National Forest, east of Featherville. That is the same drainage as Skillern Hot Springs, but a long way farther up the creek. Measured on the map, the listed coordinates are a little over 5 miles upstream of Skillern in a straight line, and the trail distance will be longer.

The honest summary: very little is known about the soak. The spring is named in inventories and the coordinates sit beside Big Smoky Creek on OpenStreetMap, but reliable trip reports are scarce. Idaho’s most thorough hot springs site, which documents nearby Skillern and Baumgartner in detail, has no trip page for it. There is no dependable published temperature, no confirmed description of the pool, and no recent report of anyone soaking there.

The spelling also varies. The creek, the guard station and the road are all “Big Smoky” on maps. The spring’s listed name is “Big Smokey”. Both refer to the same area.

So go for the country rather than the soak. Upper Big Smoky Creek is high, quiet and remote, in the Smoky Mountains between Featherville and Ketchum. If you find a usable pool, treat it as a bonus. If you want a known, rewarding soak, stop at Skillern on the way.

Getting there

The Big Smoky Creek drainage is reached from Forest Road 227, the long dirt road that links Featherville with Ketchum.

• From Featherville: Drive east on FR 227 past Baumgartner Hot Springs, which the Forest Service puts about 11 miles out of town. Continue east along the South Fork Boise River until Big Smoky Road (FR 085) branches north. Follow it to its end near the Canyon campground area, where the trail up Big Smoky Creek starts.
• From Ketchum: Take Warm Springs Road west. It becomes FR 227 and crosses Dollarhide Summit before dropping into the South Fork Boise drainage. Watch for Big Smoky Road heading north.

FR 227 is a dirt road with washboard and dust in summer. Cars and RVs regularly reach Baumgartner in dry weather. Beyond that, road conditions vary from year to year, so drive slowly and turn around if it gets rough. Check road and fire status with the Fairfield Ranger District of the Sawtooth National Forest (208-764-3202) before you go.

From the trailhead, the trail on OpenStreetMap follows Big Smoky Creek north and then east. Skillern Hot Springs, a couple of hours up the trail, is the obvious first stop. Trip reports on Skillern advise taking the high-water route to avoid repeated fords. Beyond Skillern the trail continues up the main creek, past side trails up Skillern Creek, Barlow Creek and the North Fork of Big Smoky, toward the upper basin where Big Smokey is listed.

Carry a topo map or a GPS track with the listed coordinates. Without a reliable route description, plan for slow going, possible deadfall and stream crossings, and the chance that you will not find a soakable pool.

When to go

The seasonal forest road closes from about October to mid-May, with opening usually around late May depending on snow. That sets the outer limits.

Early summer is still not ideal. Snowmelt runs Big Smoky Creek high and cold into July, and crossings get dangerous. Trip reports for Skillern name late July through fall as prime soaking season, and the same window applies, with even more reason, to a spring farther up the drainage.

September is probably the best month: lower water, fewer bugs, cool nights. It is also hunting season, so wear bright colors.

Rules and etiquette

• No fee is known for the trail or the spring. Campground fees apply at developed campgrounds along FR 227.
• Leave no trace. There are no facilities past the trailhead. Pack out all trash and bury human waste at least 200 feet from water.
• No soap or shampoo in any hot spring pool, including biodegradable products.
• Wear a swimsuit. Sawtooth National Forest order 0414-00-033 bans public nudity on all forest land and roads from September 9, 2026 to September 9, 2031, even at remote springs like this one.
• Do not build new pools or dam the creek. Small, little-visited springs are easily damaged.
• Motor vehicles: Some trails in the area are closed to motorized use, including the Skillern Creek trail. Check the current motor vehicle use map.

Where to stay nearby

• Canyon campground area: A Forest Service campground with toilets sits at the trailhead, according to Skillern trip reports.
• Primitive sites: There are primitive campsites up and down the creek near Skillern, and dispersed camping is generally allowed on Sawtooth National Forest land away from developed sites.
• Baumgartner Campground: About 11 miles east of Featherville on FR 227, with 39 reservable sites, vault toilets, drinking water and its own developed hot spring pool. It usually opens mid-May to September 30.
• Featherville and Pine: Small lodges, cabins and basic services. Ketchum and Sun Valley, over Dollarhide Summit, have the most lodging in the region.

Safety notes

• Remoteness: This is a long way from help, with no cell signal. Tell someone your route, carry a satellite messenger if you have one, and set a firm turnaround time.
• Route finding: With little current information, assume the trail may be faint or blocked in places. Carry a map and compass or a GPS track, and know how to use them.
• Creek crossings: Do not cross Big Smoky Creek during high water. Unbuckle your pack and use poles.
• Hot water: An unvisited spring can be scalding at the source. Test with a hand before getting in, and keep your head above the water.
• Wildlife: Deer, elk and moose are common in this part of the forest. Store food properly if you camp.
• Weather: Afternoon thunderstorms are common in summer in the high country. Get off exposed ridges early.