Boat Box Hot Spring

Challis, Idaho, United States

Location: Challis, Idaho, United States
Water type: iron-rich
Temperature: 38 °C
pH: 6.3

Water profile

Thermicity

Neutral

38 °C

LowHigh

Soothing — neither hot nor cold, perfect balance.

Mineralisation

Bio-active

LowHigh

Rich in active gases or metals — a strong mineral character.

Buoyancy

Standard buoyancy

LowHigh

Soft water — natural, classic buoyancy.

FerBicarbonatesManganèse

Boat Box Hot Spring, also known as Elkhorn Hot Spring, is a hot spring located along the Salmon River in the Sawtooth National Forest on Idaho State Highway 75, about 3 miles away from the town of Stanley, Idaho. The hot spring is composed of a single metal tub that is fed through a plastic tube built into the riverbank. The spring is named for the historical wooden tub that was used before it was destroyed by annual spring flooding. The average temperature of Boat Box Hot Spring is usually around 110°F (43.33°C). The water is usually not clear, as algae inhabit its waters.

Insider tip — Boat Box Hot Spring is a single-person soaking box bolted to a cliff face above the Salmon River in central Idaho's Frank Church Wilderness, fed by thermal water at a scorching source temperature that cools to a perfect 38°C in the wooden box. The access trail follows the wild Salmon River corridor through ponderosa pine forest, often with rafters floating past below. The intimate scale of the soaking box — essentially a wooden coffin perched above a whitewater canyon — makes it one of Idaho's most quirky and beloved hot spring experiences. Bring river sandals as the trail involves a short water crossing.

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