Quick FactsOverview
About Lower Loon Creek Hot Spring
Lower Loon Creek Hot Spring, Idaho is a backcountry geothermal spring along Loon Creek in the Frank Church River of No Return Wilderness in Custer County, near where Loon Creek joins the Middle Fork of the Salmon River. The spring surfaces at approximately 120 degrees Fahrenheit. A wooden soaking tub has been constructed at the site with views of Loon Creek and the surrounding wilderness. Challis, the Custer County seat on Highway 93, is the nearest town with services, though it is many miles of wilderness away.
Lower Loon Creek is one of six hot springs along the first 52 miles of the Middle Fork of the Salmon River, making this stretch of Wild and Scenic River one of the finest geothermal corridors in Idaho. The other five are Trail Flat, Sheepeater, Sunflower, Whitey Cox, and Hospital Bar. The spring is approximately 1.5 miles up Loon Creek from its confluence with the Middle Fork. The area has been used by indigenous Shoshone and Nez Perce people for centuries. This is one of the more scenic natural hot springs in Idaho, set deep in wilderness.
The wooden tub and surrounding area are maintained by visiting rafters and hikers.
Location & Access
Getting to Lower Loon Creek Hot Spring
Lower Loon Creek Hot Spring is located approximately 1.5 miles up Loon Creek from where it joins the Middle Fork of the Salmon River in the Frank Church River of No Return Wilderness. The spring is accessed primarily by permitted rafting trips on the Middle Fork, with a short hike up Loon Creek from the river to the hot spring.
The most common access for the Middle Fork float is the Boundary Creek put-in, reached via a long drive on Forest Road 568 from Stanley. River permits are required and allocated by lottery through Recreation.gov. The permit season runs from late May through September. Loon Creek Hot Spring is typically reached on the third or fourth day of a multi-day float.
Alternative Access
Backcountry hikers can reach the Loon Creek area via the 100-mile Middle Fork trail or by flying into backcountry airstrips in the Frank Church Wilderness. For visitors seeking hot springs near Challis, the Middle Fork corridor offers the densest collection of wilderness hot springs in Idaho. Sunflower Hot Springs (149 degrees source, waterfall shower feature) and Sheepeater Hot Springs (three pools from hot to comfortable) are other popular stops on the same river trip.
Suitability & Accessibility
Who Should Visit Lower Loon Creek Hot Spring
Lower Loon Creek Hot Spring suits experienced river runners and wilderness adventurers on multi-day Middle Fork of the Salmon River trips. At 120 degrees Fahrenheit, the source water is hot and may need to cool before comfortable soaking. The wooden tub provides a comfortable soaking structure with views of Loon Creek, and the 1.5-mile hike from the river is a pleasant walk through the wilderness.
Reaching the spring requires either a permitted rafting trip (lottery-allocated, highly competitive) or a long backcountry hike on the Middle Fork trail. This is not a day trip destination. The Middle Fork of the Salmon is a Wild and Scenic River with Class III and IV rapids, requiring whitewater experience or a guided trip.
Accessibility at Lower Loon Creek Hot Spring
The spring is not wheelchair accessible. The terrain is remote wilderness with no facilities beyond the visitor-maintained wooden tub. Those exploring natural hot springs Idaho offers near Challis who want easier access should visit Challis Hot Springs (commercial facility in town) or Sunbeam Hot Springs (roadside on Highway 75 near Stanley), both of which offer comfortable soaking without the commitment of a multi-day wilderness trip. The Middle Fork experience, while demanding, is one of the finest river journeys in North America.
Safety & Etiquette
Lower Loon Creek Hot Spring Safety Tips
Lower Loon Creek Hot Spring surfaces at approximately 120 degrees Fahrenheit, which is hot enough to cause burns. Test the water in the wooden tub before entering. The tub temperature depends on how recently it was filled and how much the water has cooled. Wait for the water to reach a comfortable temperature before soaking.
The Middle Fork of the Salmon River is a Wild and Scenic River with Class III and IV rapids. All rafting participants should have whitewater experience or be part of a guided trip. River permits are required and allocated by lottery. The 1.5-mile hike up Loon Creek from the river crosses unimproved terrain.
Wilderness and Wildlife Safety
Black bears, mountain lions, wolves, and rattlesnakes are present in the Frank Church Wilderness. Store food in bear-resistant containers. Make noise on trails. The Loon Creek drainage supports diverse wildlife including elk, deer, and bighorn sheep. Animal encounters are common in this remote wilderness.
Leave No Trace at Lower Loon Creek Hot Spring
Pack out all trash. Camp in designated sites along the river. Do not alter the wooden tub beyond basic maintenance. Follow all Frank Church Wilderness and Middle Fork regulations. Cell service is not available. Carry a satellite communication device for emergencies. The nearest medical facilities are in Challis or Stanley, both many miles of wilderness away. The remoteness of the Frank Church Wilderness means rescue response times can be very long.
