The Boise National Forest covers the mountains north and east of Boise, drained by the Boise, Payette and Salmon river systems, and it is some of the most hot spring rich country in Idaho. This collection gathers its natural soaks, from well known riverside pools near Garden Valley and Lowman to quiet backcountry springs at the end of forest roads. Check with the Forest Service for seasonal road and fire closures before heading out.
Vulcan Hot Springs is one of Idaho’s most unusual hot springs: a short hike through the Boise National Forest, in the Warm Lake area, reaches a source so strong that the US Department of Energy studied its geothermal potential for years. Its main pool was once reputedly the largest natural hot springs pool in Idaho — but a wildfire-era cave-in filled it with silt and sludge, and today, per the latest update, only one small pool remains soakable.
Trail Creek Hot Springs is a hugely popular pair of mortar-reinforced rock pools in the Boise National Forest northeast of Cascade, in the Warm Lake area. A short but steep hike from the highway pullout — across a man-made bridge over the creek — reaches two pools whose temperatures soakers fine-tune with creek water and a valved PVC feed. Expect company: usage here is extreme.
Penny Hot Springs is a small cluster of three springs in the Boise National Forest’s Warm Lake/Yellow Pine area. The main event is Penny #1 — “New Penny” — a rock- and sand-walled pool fed by a source marked by copper-colored algae, with two smaller siblings nearby: a one-person soaker downstream and Twopenny across the river.
Molly’s Tubs Hot Springs is a creekside rock pool in the Boise National Forest’s Warm Lake area — and despite the name, the tubs themselves are history. After years of overuse and abuse, the Forest Service dismantled and removed them; in their place are two shallow, seasonal natural pools where the tubs once sat.
Molly’s Toe is a small, hot spring in the Boise National Forest northeast of Cascade, in the Warm Lake area and part of the Molly’s hot springs cluster. Keep expectations calibrated: with a partially collapsed rock wall and a light flow, this one is a foot soak at best — a curiosity on a Molly’s-area springs tour rather than a destination soak.
Molly’s Hot Springs is a log-dam and rock-bordered pool in the Boise National Forest’s Warm Lake area, a quarter-mile from the forest road — the best-known soak of the Molly’s cluster, close enough to the road to stay popular but far enough to feel like a real find. Its temperature is adjustable via a hose-and-valve system fed from the source.
Mile-16 Hot Springs — better known to regulars as Fire Crew (and sometimes Sugah) — is a single rock-mortared pool beside the South Fork Salmon River in the Boise National Forest, northeast of Cascade in the Warm Lake/Yellow Pine area. Not to be confused with the unrelated Fire Crew Hot Springs near Crouch: this one’s nickname comes from the Krassel workstation fire crew that built the soak in 1980–81, and “Mile-16” dates from when the road was unpaved and the spring sat exactly 16 miles down it.
By Golly Molly Hot Springs — also known as Molly’s Trolley — is a pair of well-built rock pools in the Boise National Forest northeast of Cascade, Idaho, in the Warm Lake area and part of the greater Molly’s hot springs cluster. It comes with an honest caveat: despite the solid construction, there has historically been no actual soak here.
Bernard Warm Springs — also known as Smalley — is a long-forgotten warm spring in the Boise National Forest near Cascade, Idaho. Once a full-fledged hot springs resort, its seldom-used pool now sits inside the remnants of the old resort’s foundation, soaking at a mild 98°F.
Skinnydipper Hot Springs is a natural hot springs above the Banks-Lowman Highway in the Boise National Forest, reached by a steep 0.5-mile hike. It is closed to all use under a BLM closure order extended through February 2027.
Boiling Springs Hot Springs sits beside the historic Boiling Springs Guard Station at the end of a forest road north of Crouch, Idaho, in the Boise National Forest. Its rock-walled pools are fed by one of the most powerful geothermal sources in the Garden Valley backcountry.
Bonneville Hot Springs is a natural hot springs in the Boise National Forest, 19 miles southeast of Lowman, Idaho, reached by a 0.25-mile trail along Warm Springs Creek. User-built rock-walled pools and a private soak shack with a cast-iron bathtub sit below the Bonneville Campground.
Fire Crew Hot Springs is a set of user-built, rock-walled soaking pools on the Middle Fork of the Payette River in the Boise National Forest, north of Crouch, Idaho. The road is snow-covered until about late May, and the pools submerge during spring runoff.
Kirkham Hot Springs is a popular Forest Service hot springs on the South Fork of the Payette River near Lowman, Idaho, known for its shallow rock pools and hot waterfalls. Day use is free; the site is open 7 AM–9 PM with no overnight camping.
Rocky Canyon Hot Springs is a series of tiered, user-built pools on the far bank of the Middle Fork of the Payette River, north of Crouch, Idaho. Reaching them requires a cold ford of the river; the pools are best after spring runoff.
Pine Flats Hot Springs is a string of natural hot pools beside the South Fork of the Payette River near Lowman, Idaho, reached by a 0.25 to 0.75-mile hike from Pine Flats Campground. The pools are usable all winter.
Campground Hot Springs is a roadside soak on the South Fork of the Payette River, across the Banks-Lowman Highway from Hot Springs Campground east of Garden Valley, Idaho. Its main rock-lined pool runs about 110°F, reached by a staircase from the road.
Little Anderson Hot Springs, near Garden Valley, Idaho, was once a stellar, locally kept soak in the Boise National Forest. Today the pool and primitive sites are heavily damaged by ATV use and trash; visit with low expectations.
