JACKSON, Wyo. — Hot springs are a geothermal phenomenon of the western landscape, and Wyoming is home to many of these therapeutic and culturally significant features.
People have enjoyed soaking in mineral pools, which are heated within the earth’s interior, for centuries. As water passes through rock layers on the earth it can accumulate natural trace minerals, including calcium, chloride, iron, magnesium, potassium, silicate, sodium, lithium and sulfate. It is believed that the high mineral content of the water, once absorbed into the body, boosts overall oxygen flow and circulation and in combination with heat, creates healing properties.
According to the National Park Service, in volcanic areas, water that comes in contact with magma-heated rock can produce superheated water so hot that immersion can result in injury or death. In non-volcanic areas, the temperature of rocks within the Earth also increases with depth — known as the geothermal gradient. If water percolates deeply enough into the crust and comes into contact with hot rocks, it can circulate to the surface to form hot springs. The temperature of hot springs varies greatly, depending upon the water’s proximity to magma rock.
One of the main features of Yellowstone National Park is its abundant thermal activity, with more than 500 geysers and numerous hot springs. The park sits atop an active volcano, which creates a constantly changing landscape. According to the United States Geological Survey, hot springs emerge in Yellowstone as hot as 198°F and steam vents can be as hot as 275°F. While most of Yellowstone’s hot springs do not allow for soaking, the waters have led to breakthroughs in medicine and become a source of energy for buildings and fish hatcheries in the park. Boiling River, which is about 140°F at its source, does allow for soaking in certain areas where the water is cooler.
The thermal features in Yellowstone are believed by some historians to hold spiritual and cultural significance to the Native American people who once lived there. According to Karen Warren, author of “Secret Bath,” there is evidence that Tribes made use of the springs for cooking and bathed in the water for medicinal purposes. On occasion, they also buried their dead in the bubbling water.
For thousands of years, the smoking waters of Big Horn Hot Springs were considered sacred to the Native American Tribes living in the region. According to the Wyoming Historical Society, with the rise of disease and the extermination of the buffalo, Tribes were pressured to sell reservation lands. In 1896, the Eastern Shoshone and Northern Arapaho Tribes agreed to the sale of the land surrounding Big Horn Hot Springs to the federal government, now known as Thermopolis, for $60,000.
This region became Wyoming’s first state park, the Big Horn Hot Springs State Park in 1897. The treaty included a sale agreement with the tribes to always allow free access to the mineral springs. Today, the park’s free bath house is open to the public year-round and the water is maintained at 104°F for therapeutic bathing.
Saratoga Hot Springs, located in southern Wyoming, also holds a rich history; it’s believed that the thermal features of the North Platte River Valley attracted the first settlers to the area. The hot springs were considered neutral territory and the Cheyenne, Ute and Arapaho frequently soaked in this “place of magic waters.” Saratoga Hot Springs ranges from 101°F to 110°F.
Locally, Astoria and Granite Hot Springs attract people from all over and these thermal waters can be accessed throughout the year. Astoria Park Conservancy has six temperature-varying, man-made pools filled by the natural springs nearby.
Past and present, Wyoming’s mineral-rich thermal springs continue to be hot spots for warmth and healing.
This story originally appeared in the 2024 Locals’ Guidebook. Pick up a copy of the 2025 Locals’ Guidebook today!
