Giant Springs

Giant Springs is a large first magnitude spring located near Great Falls, Montana and is the central feature of Giant Springs State Park. Its water has a constant temperature of 54 °F and originates from snowmelt in the Little Belt Mountains, 60 miles away. According to chlorofluorocarbon dating, the water takes about 3,000 years to travel underground before returning to the surface at the springs.

Giant Springs is formed by an opening in a part of the Madison aquifer, a vast aquifer underlying 5 U.S. States and 3 Canadian Provinces. The conduit between the mountains and the spring is the geological stratum found in parts of the northwest United States called the Madison Limestone.