Wyoming is full of surprises! They claim to have the world's largest mineral hot spring at Thermopolis' Hot Springs State Park.
"Over colorful terraces along the Big Horn River at Thermopolis flows water from mineral hot springs. More than 8,000 gallons flow over the terrace every 24 hours at a constant temperature of 135 degrees Fahrenheit. The park has a free bath house where the water is maintained at 104 degrees for therapeudic bathing. Hot Springs has 6.2 miles of universally accessible trails and hiking trails. It is a full-service park with comfort stations, a Volksmarch trail, fishing, and a couple of boat docks. One of the reservable group picnic shelters is located here. Hot Springs is a day-use park.
The Hot Springs State Park bison herd is the central herd for the Wyoming State Parks. During the late fall and winter months, the park bison are fed a daily supplement to insure good health. This feeding usually occurs at 8:30 a.m., giving the off-season visitor the unique opportunity to view the "Monarch of the Plains," up close. Please remember that bison should be viewed ONLY while you remain in your vehicle.
The suspension foot bridge across the Bighorn River is commonly called "The Swinging Bridge." The bridge is a unique vantage point from which to view the Bighorn River and mineral terrace. Hot Springs State Park has long been known for its beautiful summer flower gardens. Make a point of bringing your camera with you, and capture the exciting splash of color all summer..."
Hot Springs State Park is about 150 miles south of Red Lodge, Montana and the "Beartooth Highway". Jackson, WY and Teton National Park are to the west, and Yellowstone is just north from the Tetons.