Amatlán de Canas, Nayarit, Mexico barely qualifies as a hot spring to me, though some would consider it so. The water at Amatlán is 37 degrees Centigrade or 98.6 F. Still it is pretty country at 5,000 feet. And there are many people who believe that the healing properties of waters are just as efficacious at cooler temperatures.
Amatlán de Canas is off the main highway MEX-15 between Tepic, Nayarit and Guadalajara, Jalisco, at Ixtlan del Rio, Nayarit. It's 143 kilometers (90 miles) from Guadalajara to Ixtlan, then then 14 kilometers to Ahuacatlan. There turn south for 33 KM to Amatlán de Canas.
The small hotel, Arena is owned by friendly folks. Los Pavorreales is better-known. Both are relatively inexpensive, with the former about $25 and the later about $45. El Monto with a waterfall and cooler water is nearby.
Travel Medical Insurance, Expat Insurance up to Age 75, Medical Air Evac - reasonable price.
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