Ennis Hot Springs
Ennis Hot Springs registers at 181°F, making it one of Montana's hottest thermal sources and far too hot for any direct contact. The spring sits at 4,907 feet elevation, 32 meters from Snipe Lane in Madison County. Water chemistry shows a balanced mineral signature with 50 mg/L calcium, 20 mg/L magnesium, and 25 mg/L sodium at pH 7.7.
The spring emerges in the broad Madison Valley, flanked by the Madison Range to the east and the Tobacco Root Mountains to the west. The valley floor is a patchwork of irrigated hay fields, cattle ranches, and sagebrush flats at roughly 5,000 feet elevation. The Madison River, a world-renowned trout fishery, flows through the valley several miles to the east. Annual snowfall averages 70 inches, and the semi-arid climate receives about 20 inches of precipitation. The Gravelly Range rises to the southwest.
The spring's name references the nearby town of Ennis, founded in 1863 during the Alder Gulch gold rush. The USGS-measured modern temperature of 7.8°C appears to represent a mixed or distal sample rather than the source, given the 181°F historical record. The extreme temperature differential of 139°F above ambient suggests a deep-circulation geothermal source connected to regional fault systems in the Madison Valley. Specific development history of this spring is not well documented.
Do not attempt to enter or touch the water; at 181°F, it causes severe burns instantly. The spring is worth observing from a safe distance for its geothermal activity. Visit May through October when roads are clear. Axolotl Cabin, a BLM rental 18 km southwest at 7,000 feet in the Gravelly Range foothills, provides backcountry lodging. Virginia City, the historic territorial capital, is the nearest town. The Madison River corridor south of Ennis provides outstanding fly fishing.
Is Ennis Hot Springs worth visiting?
Best for
- Observing powerful hot springs
- Easy day trips
- Overnight camping trips
Not ideal for
- Casual soaking
The water at Ennis Hot Springs is slightly alkaline (pH 7.7).
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Overview The Dillon Field Office is unable to make reservations for you. Please call Recreation.gov (877-444-6777) to book a reservation or book online. Axolotl Cabin is located approximately 14 miles southwest of Ennis, Montana, in the foothills of the Gravelly Range. The cabin provides access to a variety of outdoor recreational activities and breathtaking views as it peers over the Madison Valley. The cabin is at an elevation of about 7,000 feet and is adjacent to Axolotl Lakes Wildernes...