Inside the only natural vapor cave in Colorado

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It’s over 110 degrees inside the cave, with 100% humidity. Three natural chambers are connected by a tunnel shored up with concrete and bricks. Photo: Amanda Horvath, Rocky Mountain PBS
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GLENWOOD SPRINGS, Colo. — Colorado is home to more than 100 hot springs in Colorado. But next door to Glenwood Hot Springs — and 30 feet underground — sits a natural vapor cave, the only one like it in the state.

Alex Delomonico operates Yampah Spa and Vapor Caves, the business situated above the unique geologic feature. He thinks of his role more as a stewardship, taking care of what he says is the only natural vapor cave in North America.

Delmonico and his family bought the business in 2022. One of his favorite things about the job is explaining the vapor caves to visitors who’ve never heard of them.

“You've got three different chambers that were carved out by the hot springs over millions of years. The spring itself does come up in one of those chambers, and the water then flows around the perimeter of the room,” Delmonico said of the natural sauna that he has been visiting since he was 10 years old.

It’s over 110 degrees inside the cave, with 100% humidity. Three natural chambers are connected by a tunnel shored up with concrete and bricks. The minimal light and saturating heat create a feeling of security, not confinement. 
The steps leading down to the 110 degree cave. Visitors are greeted by a sign asking them to respect the quiet of the caves and speak in low tones. Photo: Alexis Kikoen, Rocky Mountain PBS
The steps leading down to the 110 degree cave. Visitors are greeted by a sign asking them to respect the quiet of the caves and speak in low tones. Photo: Alexis Kikoen, Rocky Mountain PBS
Ute Indians would travel from all around the region to use the caves as a place of healing before the federal government forcibly removed them from Colorado in 1881. Warriors would visit the caves after battle to heal their wounds and pray, according to Adam Shavanaux, a member of the Ute Indian Tribe in northeast Utah.

“If you were sick and you didn't feel good, we would go [to Glenwood Springs,] and it was a natural place to go along with the vapor caves. Those vapor caves are like our sweat lodges, going back into Mother Earth,” said Cassandra Atencio, tribal historic preservation officer for the Southern Ute Indian Tribe.
 
In the late 1880s, prospectors and entrepreneurs descended on the area as the U.S. Army removed the Ute people. The mineral water at the hot springs and in the caves, made up of lithium, sulfur and magnesium, attracted early residents of Glenwood Springs and workers from nearby mining towns such as Aspen and Leadville.
 
Three separate caves sit at the confluence of the Colorado and Roaring Fork rivers. Cave No. 3 is what Yampah Spa and Vapor Caves was built on in 1893 and is still the main draw of the business today. Cave No. 1 sits to the south, across the Colorado River. This was the original attraction at the turn of the century, but eventually closed following the construction of the Denver and Rio Grande railroad — trains hit and killed visitors as they walked on the tracks to access the cave.
An undated photo hanging in the hall at Yampah Spa shows the old Cave No. 1 building and entrance, right next to the railroad tracks on the southern side of the Colorado River. Photo courtesy Yampah Spa and Vapor Caves
An undated photo hanging in the hall at Yampah Spa shows the old Cave No. 1 building and entrance, right next to the railroad tracks on the southern side of the Colorado River. Photo courtesy Yampah Spa and Vapor Caves
Cave No. 2 wasn’t really a cave at all. It was more of a mine shaft. According to Richard Rhinehart, digital editor of Rocky Mountain Caving, the owners of Yampah Spa built it to handle extra visitors when Cave No. 1 was full. Rhinehart is the author of “Wonderful Places,” a book on the history of caves in the Glenwood Springs area.
 
“The big initial attraction in the city for any sort of tourism, they were going to the vapor cave because that was, even then, considered a unique attraction and something healthy and something worth going to,” he said.

Because of the hot springs, all the grottos in the area, such as Fairy Caves, Cave of the Clouds, and Hubbard’s Cave, likely all had a sauna-like quality at some point over the millennia.

“You have what's known as a mixing zone cave, where you have the water coming down through cracks from rain and snow melt up above, but you also have the warm water coming up and the two of them together can be really powerful at chemically eroding out these cave passages,” said Rhinehart, of how the caves are different from others in the country.

“That's why you have some really unique geologic features in not only vapor cave number one, but also in Glenwood Caverns,” he said.

The vapor caves have their own part in Glenwood’s unique history. During World War II, the U.S. Navy took over the Hotel Colorado to use it as a recovery hospital. Needing more room, physicians also put patients in what is now the massage rooms at Yampah Spa, according to Delmonico.  
The business in 2025, top, and in the last century. The undated bottom photo hangs inside Yampah Spa and Vapor Caves, showing the original building that’s been added to over its 100 plus years in business. Illustration: Joshua Vorse, Rocky Mountain PBS
The business in 2025, top, and in the last century. The undated bottom photo hangs inside Yampah Spa and Vapor Caves, showing the original building that’s been added to over its 100 plus years in business. Illustration: Joshua Vorse, Rocky Mountain PBS
“It's a place where people come to meditate and relax and heal. And when you're in that space and you see those caves, you see the rock, you feel the heat and the moisture and those minerals on your body, and you hear that water running, you know immediately you're in another world,” said Delmonico.

Shavanaux recently visited Yampah Spa and Vapor Caves to give a blessing for the spring equinox. His people were forced out of Colorado and into the Uintah and Ouray reservation in Utah.

“To me, that's going back home, being there [at the caves.] And then to go back and to be welcome there and to be treated so great by the people that are there now, it makes you feel good,” said Shavanaux, who does ceremonies at his own sweat lodge on the reservation.

Delmonico says maintaining relationships with members of the Northern and Southern Ute tribes is important, and he hopes to honor how special the vapor caves are to them.

“All they have to do is show an identity card that they are indigenous and we let them in free of charge. And we also have consent communication to let them know that they are welcome here for any ceremonies, anything they want to do,” he said.

First-time visitor to the vapor caves, Stephanie Craig, said she was drawn to the feeling of rejuvenation described by frequent guests such as her father. 

“My dad comes here, I swear every day, I just kind of wanted to get the experience and feel that glow that everyone keeps talking about when they leave,” said Craig, who has lived in Aspen, Rifle and now Glenwood Springs, but had never been to Yampah Spa and Vapor Caves before.

Now, as she leaves feeling hydrated, the dullness of a Wednesday afternoon gone, Craig says the vapor caves might replace a run to Target for some Tylenol next time she’s not feeling well.
Type of story: News
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
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