Quick FactsOverview
About Barth Hot Springs
Barth Hot Springs, Idaho is a backcountry geothermal spring along the Main Salmon River in the Frank Church River of No Return Wilderness in Idaho County. The NOAA thermal springs database records the source at 140 degrees Fahrenheit. The spring feeds a soaking pool on the river bank with views of the Main Salmon, often described as one of the most scenic hot spring settings in Idaho. Salmon, the Lemhi County seat on Highway 93, is the nearest town with services, though it is many river miles away.
Barth Hot Springs is a classic stop on multi-day Main Salmon rafting trips, typically visited on day two of the float. The spring is accessed by a short hike from the river to the pool. The Main Salmon River, also known as the River of No Return, is a federally designated Wild and Scenic River flowing through the second-largest contiguous wilderness in the lower 48 states. The combination of hot spring soaking with panoramic river views and wilderness solitude makes Barth one of the more memorable natural hot springs in Idaho for river runners.
The pool is primitive and visitor-maintained. Conditions vary with season and river levels.
Location & Access
Getting to Barth Hot Springs
Barth Hot Springs is located along the Main Salmon River in the Frank Church River of No Return Wilderness, accessed primarily by permitted multi-day rafting trips. The springs are typically reached on day two of a Main Salmon float, with a short hike from the river to the soaking pool.
The most common put-in for Main Salmon rafting trips is Corn Creek, located approximately 46 miles north of Salmon on Forest Road 030. River permits are required and allocated by lottery through Recreation.gov. The permit season typically runs from late June through September. Outfitters offer guided trips for visitors without their own equipment or whitewater experience.
River Trip Planning
The Main Salmon float covers approximately 80 miles through the Frank Church Wilderness, typically taking 5 to 6 days. Barth Hot Springs is one of several rewarding stops along the route. For visitors seeking hot springs near Salmon who do not have a river permit, Goldbug Hot Springs (113 degrees, a popular 4-mile round-trip hike south of Salmon) and Sharkey Hot Springs (BLM developed site, 103 degrees) offer easier access. The Middle Fork Salmon River, which joins the Main Salmon downstream, also has six hot springs along its course.
Suitability & Accessibility
Who Should Visit Barth Hot Springs
Barth Hot Springs suits experienced river runners and wilderness adventurers on multi-day Main Salmon rafting trips. The pool offers a comfortable soak with views of the River of No Return that few other hot springs in Idaho can match. The short hike from the river to the spring makes it accessible to all members of a rafting party when conditions allow.
Reaching the spring requires a permitted rafting trip (lottery-allocated, competitive) or significant backcountry travel. This is not a day trip destination. The Main Salmon has Class III and IV rapids requiring whitewater experience or a guided trip. Many outfitters include Barth as a planned stop on their Main Salmon itineraries.
Accessibility at Barth Hot Springs
The spring is not wheelchair accessible. The terrain is remote wilderness with no facilities. Those exploring natural hot springs Idaho offers near Salmon who want easier access should visit Goldbug Hot Springs (steep but rewarding 4-mile round-trip hike), Sharkey Hot Springs (BLM developed site with concrete pools and changing rooms), or Challis Hot Springs (commercial facility in Challis). The Main Salmon rafting experience is one of the finest multi-day river trips in North America, combining hot springs, Class III and IV whitewater, and wilderness camping for an unforgettable backcountry adventure.
Safety & Etiquette
Barth Hot Springs Safety Tips
Barth Hot Springs has source water at 140 degrees Fahrenheit, which is dangerously hot. Always test the soaking pool temperature before entering, as conditions change with season and river levels. The source area should not be touched directly.
The Main 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. The short hike from the river to the spring crosses unimproved terrain. The trail can be slippery when wet.
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 Main Salmon corridor supports diverse wildlife including elk, deer, bighorn sheep, and river otters. Animal encounters are possible throughout the trip.
Leave No Trace at Barth Hot Springs
Pack out all trash. Camp in designated sites along the river. Do not alter the soaking pool. Follow all Frank Church Wilderness and Main Salmon River regulations. Cell service is not available in the wilderness. Carry a satellite communication device for emergencies. The nearest medical facilities are in Salmon, many river miles away. A satellite communication device is essential for emergencies on the Main Salmon, as rescue response times in the wilderness can be very long. Pack a comprehensive first aid kit for the duration of your river trip.
