"The natural fresh-water springs at Hierve el Agua were incredible (and cold!). The water is very high in calcium carbonate, and the minerals have formed these natural pools and crazy waterfall-like rock formations. The dusty road was somewhat harrowing, we had to make way for quite a few donkeys packing some serious loads. (And the formerly white rental car came out of the experience with a light yellow coating.) But the view over the valley of Oaxaca was unbelievable, and the meal we had at one of the stands was delicious. We were there in December; it was clear and warm and perfect. By AFAR Traveler , AFAR Contributor"