Explore Colorado / Explore The Outdoors

Hike to Colorado’s Only Geyser: Geyser Spring Trail

This is a hike that’s way down a dirt road off of Highway 145 between Dolores and Telluride in the San Juan Mountains of Southwest Colorado.  I recently found out about Colorado’s only true geyser and immediately added it to my itinerary for my recent Cortez trip.  The trail is Geyser Spring Trail.  I turned on Dunton Rd/County Road 38/NFSR #535 and drove 23.3 miles surrounded by beautiful fall foliage and stunning scenery on a paved road for about 15 miles.  The last six miles or so were on a gravel dirt road that I would stay on for the rest of the drive to reconnect with Highway 145.  The trailhead is 2.2 miles south of the town of Dunton, a late 1800s mining town turned very exclusive Dunton Hot Springs resort. 

Here are some quick facts about Geyser Spring.  It’s Colorado is only natural geyser and part of a series of hot springs in the Dolores River watershed.  During the mid-Cenozoic Period, which occurred about 28 million years ago, intrusions of water into geologic faults were exposed to magma deep within the earth’s crust.  The expanding carbon dioxide gas driven by magma heated water is what gives Geyser Spring its geyser characteristics.  Eruptions vary in frequency usually in 30 to 40-minute intervals.  The boiling action lasts for about 15 minutes.  The temperature of the spring is around 82.4°F.  Carbon dioxide and hydrogen sulfide gas displace oxygen near the water surface.  You can’t swim, or even sit, in it because it could kill you.  There’s a warning sign at the geyser.

It’s 1.3 miles to Geyser Spring.  The trail starts in a picturesque setting with a small bridge over the Dolores River. 

I enjoyed the fall colors across the way then quickly hiked into some aspens, then into some pines as the trail gradually climbs.  A little less than a mile in, the trail gets rocky as you approach a switch back and get the steepest part of the hike.  I got a whiff of sulfur’s signature rotten egg smell and saw a small hole with bubbling water.  Definitely an interesting feature to see on a hike. 

After the short climb the trail turned into a series of easy rollers with really tall aspens on one side and an amazing view of other fall colors on the other.  When I hit a downhill, I could hear water, the trees opened up for an incredible view and I got my first glimpse of Geyser Spring.

Colorado’s only geyser doesn’t erupt into the sky like Old Faithful.  Instead, I think it looks like a bubbling brew in a witch’s cauldron.  The rotten egg smell is pretty pungent too.  The geyser bubbled for the 15-20 minutes I was there and at times the intensity of the bubbling increased.  The unique geologic feature is right next to a small spring.  It kind of looks like hot tub, but a deadly one because of the dangerous gases depleting the oxygen at the water’s surface.

On the hike back, I savored the colors of fall, especially the golden aspens, which are my favorite.  If you’re looking for an unique hike that’s not long or hard and filled with fall colors, Geyser Spring Trail is perfect. 

After the hike, I drove past Dunton Hot Springs and on the rough road stretch to connect back to Highway 145 instead of driving back out the way I had driven in.  The ten miles between Dunton Hot Springs and Highway 145 has some narrow spots with drop-offs and is rough in spots.  I have a Subaru Forester and was very glad to be in a vehicle with clearance in a couple of spots.  The rough ride is worth it to see the stunning scenery along the old dirt road.  As I was enjoying the gorgeous fall colors, I was dreaming of a stay at the luxurious Dunton Hot Springs so I can explore this slice of paradise in the San Juans a little more.

Author Jennifer Broome has filmed hundreds of stories in Colorado and loves finding new gems to share. She has spent a lot of time in the San Juans. Check out her blogs on Durango, Ouray and Telluride for more areas to explore in Southwest Colorado.