# Elkhorn Hot Spring, Idaho

Elkhorn Hot Spring in Idaho. 136°F (58°C). Roadside · Public Land. Custer County.

- Page: https://www.soakingsprings.com/hot-springs/idaho/elkhorn-hot-spring
- Source: Soaking Springs, researched and maintained by Armen Suny
- Updated: 2026-09-14

## Can you soak at Elkhorn Hot Spring?

Yes. Elkhorn Hot Spring has natural, undeveloped pools. Soaking is free. You can drive right up to it.

## Key facts

| Fact | Value |
|---|---|
| Source water temperature | 136°F (58°C) (USGS record; developed pools are often cooled) |
| Elevation | 6,155 ft |
| Access | Roadside · Public Land, 239 ft from the nearest road (Salmon River Scenic Byway) |
| Land | Idaho Department of Lands, SDOL |
| County | Custer County |
| Nearest town | Challis |
| Coordinates | 44.24500, -114.88500 |
| Best months to soak | December, January, February (largest gap between water and average air temperature) |
| Nearest campground | SUNNY GULCH CAMPGROUND, 4.9 mi |

## Plan your visit

| | |
|---|---|
| Type | Primitive pools |
| Cost | Free |
| Season | Year-round |
| Reservations | Not needed |
| Getting there | roadside near Hwy 75, about 3 mi from Stanley |
| In winter | roadside, tub usable all year; river pools submerged at runoff |
| Operator | US Forest Service (Sawtooth NRA) |

Checked October 2026. Sources: https://idahohotsprings.com/destinations/elkhorn/index.htm, https://en.wikipedia.org/wiki/Boat_Box_Hot_Spring

## About Elkhorn Hot Spring

Elkhorn Hot Spring, also known as Boat Box Hot Spring, is a Custer County roadside spring on the Salmon River Scenic Byway. The tub water comes in hot, mid 130s. Open access. The land is Idaho Department of Lands ground under an SRMA designation. Challis is the nearest town on file at 37 miles, though the Wikipedia entry places the spring about three miles from Stanley. For camping, the record points to Sunny Gulch Campground.

The byway passes within about 240 feet. Elevation is high and the yearly mean hovers around 40. A dozen feet of snow is a normal winter here. The spring itself is the tub Wikipedia describes, on the riverbank, so the setting is the Salmon River and the highway beside it.

Wikipedia calls this Boat Box Hot Spring and says it is also known as Elkhorn Hot Spring. The spring is a single metal tub fed through a plastic tube built into the Salmon River bank, about three miles from Stanley on Idaho State Highway 75. The name comes from a historical wooden tub that was used before annual spring flooding destroyed it.

December through February are the listed best months. A highway corridor under twelve feet of snow usually gets plowed, but find out. The water needs cooling in the tub before you get in. No chemistry is on file. Sunny Gulch is the closest camping.

## Nearby

- Nearest city page: [Hot springs near Challis](https://www.soakingsprings.com/hot-springs/near/idaho/challis), 4 mi away
- State page: [Hot springs in Idaho](https://www.soakingsprings.com/hot-springs/idaho)
- [Mormon Bend Hot Spring, ID](https://www.soakingsprings.com/hot-springs/idaho/mormon-bend-hot-spring): 100°F source, Short Walk, near Challis, Custer County, primitive pools, free, jul-oct
- [Stanley Hot Spring, ID](https://www.soakingsprings.com/hot-springs/idaho/stanley-hot-spring): 106°F source, pH 8.8, Roadside, near Challis, Custer County
- [Basin Creek Hot Spring, ID](https://www.soakingsprings.com/hot-springs/idaho/basin-creek-hot-spring): 133°F source, pH 9.5, Roadside, near Challis, Custer County, primitive pools, jun–oct
- [Sunbeam Hot Springs, ID](https://www.soakingsprings.com/hot-springs/idaho/sunbeam-hot-springs): 169°F source, pH 9.0, TDS 291 mg/L, Roadside, near Challis, Custer County, primitive pools, pools 100–110°F, free, year-round
- [Rosalys Warm Spring, ID](https://www.soakingsprings.com/hot-springs/idaho/rosalys-warm-spring): 106°F source, pH 9.4, Short Walk, near Sun Valley, Blaine County
- [Robinson Bar Hot Springs, ID](https://www.soakingsprings.com/hot-springs/idaho/robinson-bar-hot-springs): 131°F source, pH 9.4, TDS 294 mg/L, Roadside, near Challis, Custer County

## Questions

**What is the water temperature at Elkhorn Hot Spring?**
Elkhorn Hot Spring has a water temperature of 136°F (58°C). This is considered a hot spring, well above body temperature.

**Where is Elkhorn Hot Spring located?**
Elkhorn Hot Spring is located in Custer County, Idaho at 6,155 feet elevation, near Challis. Coordinates: 44.2450°N, 114.8850°W.

**How do I get to Elkhorn Hot Spring?**
Elkhorn Hot Spring has Roadside road access, with the nearest road being Salmon River Scenic Byway (239 ft from the road).

**Is Elkhorn Hot Spring free to visit?**
Elkhorn Hot Spring has Open access. It is managed by SDOL.

**Can I camp near Elkhorn Hot Spring?**
Yes, Sunny Gulch Campground is located nearby (4.9 miles away).

**Is it safe to soak at Elkhorn Hot Spring?**
With care. At 136°F Elkhorn Hot Spring is hot enough to need short sessions, fifteen to twenty minutes, and plenty of water. Enter slowly and get out if you feel light-headed.

## Sources

- USGS thermal springs records, Water Quality Portal lab analyses, OpenStreetMap, Wikipedia/Wikidata, NOAA climate normals
- https://en.wikipedia.org/wiki/Boat_Box_Hot_Spring