Radium Hot Springs - Free soaking · donation encouraged in Kremmling, CO (2026)
A single rock-walled pool tucked against the Colorado River lets rafters mix hot vents with the current after floating Gore Canyon.
Radium Hot Springs in Grand County, Colorado is a free wild riverside soak on the Colorado River about 20 miles south of Kremmling — accessed via a moderate 0.6-mile hike down from the Mugrage Park trailhead. A single rock-walled pool sits at the river's edge, fed by hot mineral seepage that mixes with cold Colorado River flow. The pool is best known among the Front Range whitewater community as the post-float soak after the Class III-IV Gore Canyon section of the Colorado. Free; a state wildlife area parking permit or America the Beautiful pass is required at the trailhead.
What to expect
Drive the rough graded-dirt road to the Mugrage Park trailhead (Trough Road from CO-9, about 30 minutes from Kremmling). Display your wildlife area permit or America the Beautiful pass on the dash. Hike 0.6 mile down a moderate trail to the river. Single pool; clothing-required by law (often-ignored), no facilities. Camping permitted at designated dispersed sites along Trough Road but not within 100 feet of the river. Best in late summer through fall when river flows are low.
Temperature
95°-105°F
Pools
1 soaking pools
Best season
May-October
Reservations
Walk-up friendly
Dog policy
Leashed dogs welcome
Family policy
Adults only
Safety notes
- High river flows can submerge the pool or sweep bathers downstream—skip it when release flows spike.
- Leave No Trace strictly enforced; rangers cite glass bottles and camping within 100 feet of the river.
Amenities & etiquette
FAQ
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Editor’s picks nearby
- The Springs Resort in Pagosa Springs — 25 mineral pools terraced down to the San Juan River, fed by the 1,000-foot-deep Mother Spring — $79 timed-entry day passes, the most refined of the major Colorado resorts.
- Strawberry Park Hot Springs — the Steamboat-area cult favorite — six stone-bordered pools tucked in aspen forest.
- Valley View Hot Springs — the clothing-optional San Luis Valley nature preserve — multiple pools and a sauna deep in the Sangre de Cristo foothills.