It doesn't end with the traditional hot spring pools that are common in the countryside.
Think you've been tricked, and pay the extra fee to sneak into the vinyl house in the back.
Great Sand Dunes National Park
Newly established in 2004, the newest national park in the United States is the highest elevation sand dune in North America.
Christian Collins - mt herard from dunefield (2017) CC BY-SA 2.0
The dunes formed in this region, which is not particularly arid, because the strong westerly winds coming over the Rocky Mountains carry sand that collides with another mountain range.
The area overlooking the dunes has an abundance of hot springs.
The Colorado Gators Reptile Park, a facility that uses the thermal water, is also located nearby.
Regular pool for kids
Sand Dunes Swimming Pool & RV Park is, as the name implies, an RV park/campground with hot springs.
Use of the pools for overnight guests is not free, but half the normal price.
Since it was a walk-in this time, I paid the $15.00 adult fee (as of this writing) to enter.
There I found a somewhat nostalgic scene.
Facing the huge Main Pool was a covered area.
On the side of the main pool was the Baby Pool, and on the other side was the Therapy Pool.
The water temp in the Main Pool was 100 degrees F and the therapy pool was 106 degrees F.
On the other hand, the temperature at the source appears to be 118 degrees F.
There was a water slide, which kids may enjoy.
Greenhouse for adults
Here is where the fun begins.
Once I have completely exited, I went around to the back of the facility.
A greenhouse that once grew vegetables served at the restaurant has been renovated and turned into an adults-only spa facility.
There was an age limit of 21+ and a $5.00 surcharge.
To the right, just inside the door, was a row of golf simulators.
Proceeding to the left, the interior of the plastic house was finally revealed.
The first thing that caught my eye was the "coffin" near the entrance.
The pool was shaped like a coffin, and 111 degrees F water was poured into it.
Suppressing my impatience, I first paid the fee.
This cool bar was the reception desk, which also serves alcoholic beverages and food.
Alcoholic beverages are limited to three drinks per person, as drinking and getting warm can make you dizzy.
The Zero Entry Pool bisects the vast interior.
It was long and narrow, gradually deepening as one went deeper.
An untouched area remained at the far end of the greenhouse, which was undergoing renovation.
Walking along the boardwalk surrounded by tropical plants, I felt as if I were strolling through a botanical garden.
I found a sauna hidden in the bushes.
The interior was sized to accommodate about 10 people.
Including the Coffin Tub mentioned earlier, there were a total of three small pools.
This Deep Thought Tub had a temperature of 108 degrees F.
It seemed that natural thermal water was indeed fed from the water outlet.
However, all the pools had a faint or obvious odor of chlorinated chemicals.
It might be that there happened to be detergent left over after cleaning, but this foaming may well raise a question.
While the originality of the space was wonderful, the water quality was unsatisfactory to me.
Drainage was done through ditches that imitated natural streams.
Sand Dunes Swimming Pool & RV Park, Hopper, Colorado, U.S.
Type: Walk-in, Logging (campground)
Rule: Clothing required
Water temp: Up to 118 degrees F