Near the town of Aconchi, in the state of Sonora, Mexico there is a fault line that spews forth hot water. Not just a little bit, but a large amount of hot water. Some time in the past a visionary with an idea developed a series of channels to move that hot water through various pools. These aqueducts provided numerous “private” pools for guests and also regulated the temperature in each once.
Since then there have been large swimming pools added. Bathrooms with flush toilets. Picnic tables. BBQ grills. A caretaker. A couple of semi-wild horses. Hundreds of yellow butterflies. And still, the channels of hot water gurgle on.