Hierve el Agua – Spanish for "the water boils" – are natural mineral springs located on a clifftop, about a 90-minute drive from Oaxaca City. Along with swimming in the warm springs, visitors can hike on paths above and below Hierve el Agua's petrified mineral falls. 

Recent visitors raved about the beautiful views and warm springs, though they warn that travelers should be prepared for some strenuous hiking and strong sunshine. Some recommend hiring a tour to serve as both the transportation and guide, which can be booked at most Oaxaca City hotels.  

If you don't book through an organized tour operator, you'll have to pay a few small fees to drive through the village and to enter the natural attraction. Hierve el Agua is located 40-some miles southeast of Oaxaca City, but the drive takes around 90 minutes. For more information, check out Visit Mexico's website.