Durango has a mystery in its midst: the Pinkerton Hot Springs.
Travelers pass the springs heading north on U.S. Highway 550, and some area residents are curious enough to stop the car to check it out. But not many people know how the red-tinted rock pile was formed or where the hot water comes from.
Hot springs are scattered across Colorado, but the Animas Valleys springs are unique in the way they are formed, said David Gonzales, a geology professor at Fort Lewis.
There are fractures in the ground where water from snowmelt and rainfall move into the cracks and down toward the Earths core. The water travels thousands of feet underground and reaches a point where it cant travel any further. There, it circulates back to the surface, dissolving rocks and creating a hot spring.
The Pinkerton water, which eventually empties into the rock pile past Hermosa on Highway 550, is all natural, but the rock pile was built by the Colorado Department of Transportation about 10 years ago to give it a safer place to discharge.
The hot spring originally emptied on the west side of the highway and traveled down the ravine by the highway. CDOT built the rock pile on the east side of the highway with a pipe in the middle of it to stop the water from destroying vegetation on private property, said CDOT spokeswoman Nancy Shanks.
No research has been done to determine how long it takes for the seepage to travel below ground and back, but Gonzales estimates that it takes about a month.
Depending on how many fractures there are and how open they are, it could take a relatively short period of time, he said.
The waters temperature at Pinkerton ranges between 95 and 105 degrees Fahrenheit. Gonzales said there are two theories scientists have for how the water is heated.
The water could simply be heated as it goes further into the Earths core while it circulates, or the water could reach magma, which would heat the water faster because of the extreme heat.
While the rock pile is all passersby see now, Pinkerton has a history dating back to the early 1800s, when James Harvey Pinkerton turned the hot springs into a travel destination.
Hot springs, including Pinkerton, were thought to have healing powers in the 1800s. People bathed in the springs, drank the water and looked for a cure to aches and pains and other ailments, said Duane Smith, a history professor at Fort Lewis College.
In the 19th century, hot springs were the miracle cure, Smith said.
This made our area a kind of health mecca, Smith said.
According to a sign posted next to the hot springs with its history, water from the spring was served in restaurants in 1892.
James Pinkerton built a resort with a hotel and a swimming pool filled with the water. The hotel burned down three times, but Smith said Marilyn Monroe supposedly stayed at the resort before the hotel burned down for the last time. The resort occupied the space where Colorado Timberline Academy currently sits.
The resort also served as a speakeasy (a place that illegally sold alcohol) during the prohibition in the 1920s.
The hot springs may not be the national attraction they once were, but Pinkerton still gives travelers pause.
Shannon Myers moved to Durango about six months ago and first saw the spring on Sunday while traveling to Silverton.
We had no idea what it was, but we wanted to stop by on the way back and take a look, she said.