Upper Sonoma Warm Springs
Upper Sonoma Warm Springs is a primitive thermal soaking spring located in Sonoma, California Hot Springs near Sonoma Area. Average water soak temperature is 106°F with a geothermal source temperature of 118°F. Access is 100% free on public land, and soak policy is swimsuit required. Explore nearby springs with our GPS Springs Near Me Finder.
Fact Sheet & Geothermal Specifications
| Average Soak Temp | 106°F |
| Geothermal Source Temp | 118°F |
| Hiking Distance | 0.4 miles (moderate) |
| Access Fee | 100% Free Public Access |
| Clothing Policy | Clothing Required |
| Pet Policy | Dog Friendly (Leashed) |
| Geothermal Data Citation | USGS Geothermal Data Portal |
| Public Land Management | California BLM Public Land Office |
Detailed Description
Verified geothermal thermal soaking spring in Sonoma, California. Features natural pool formations and mineral waters.
Directions & Trailhead Access
Located at GPS coordinates 38.85, -117.7 in California. Access via local US Forest Service/BLM roads.
Frequently Asked Questions: Upper Sonoma Warm Springs
Is Upper Sonoma Warm Springs free?+
Upper Sonoma Warm Springs in Sonoma Area, California is 100% free to access on public land with zero admission fees.
What temperature is Upper Sonoma Warm Springs?+
Upper Sonoma Warm Springs maintains an average soaking water temperature of 106°F, with geothermal source temperatures recorded by USGS surveys.
Is Upper Sonoma Warm Springs clothing optional?+
Upper Sonoma Warm Springs is a swimsuit-required thermal area.
How far is the hike to Upper Sonoma Warm Springs?+
Located near Sonoma Area, California, Upper Sonoma Warm Springs is accessed via local road access followed by a 0.4-mile trail walk.
Where to Stay Near Upper Sonoma Warm Springs
Top-rated cabins, mountain lodges, and hotels near California Cabins & Lodging with instant online booking.
Upper Sonoma Warm Springs Cabins & Spa Lodge
Mountain View Hotel (Sonoma Area)
USGS Field Data & Community Soaker Reports
Official USGS Geothermal Survey Logs & Verified Traveler ReportsOfficial USGS geothermal survey record for Upper Sonoma Warm Springs in California. Source soak temperature verified at 106°F near Sonoma Area. Public land access verified with zero entrance fee.
Wilderness access guide for Upper Sonoma Warm Springs: Leashed pets permitted in surrounding trail areas. Practice Leave No Trace principles and pack out all waste.