Hierve el Agua, translated as water boils, is a site known for its dramatic ‘petrified waterfall’ rock formations and mineral springs; located high in the mountains surrounding Oaxaca. The area is also important from an archaeological perspective because of the terraces built by the Zapotec people around 2,500 years ago for crop irrigation (unique in Mexico).
The calcified waterfalls and other above ground forms are actually created by underground-fed springs over time in much the same way as stalactites are created in caves – this water contains an abundance of calcium carbonate which then builds up over thousands of years to create fantastic rock formations. You can see the spring water still bubbling up through the rock in different areas as you walk around the site. It is this bubbling motion that gives Hierve el Agua its name.
Actually getting to Hierve el Agua is an undertaking in itself as it is located about 70km away in an isolated area in the mountains outside Oaxaca. From Oaxaca, you have a couple of transport options: small van, taxi, colectivo or bus tour.
Colectivo is probably your cheapest but arguably worst option. You should probably factor in this excursion as an all-day trip as you will need to take about 3 separate colectivos, and each time you will also need to wait in the sun at the crossroads for the next one in your relay.
Regardless of your choice of transport, you will travel up a winding, narrow, dirt and rock road up the side of the mountain range passing large trucks on blind corners and staring out your window at the very steep dropoff before you travel through San Lorenzo Albarradas and San Isidro Roaguia – the 2 villages on the road to the site, pay the state government toll (based on number of car occupants) and you are there!
Hierve el Agua, once you have torn yourself away from the vendors selling refrescos and taquitos in the hot sun, is found down a dusty path. The site has several artificial pools people can bathe in, sunbathe next to (or apparently apply sunscreen in based on the oil-slick in the smaller pools). The spring water (not for drinking) is reputed to have rejuvenation qualities so it formed part of many Zapotec healing ceremonies. Today you can go and spend time splashing about in the pools as a relief from the heat – be warned that the water is weird colours due to the high mineral content.
The site is pretty dramatic, with one of the larger (artificial) pools creating an infinity pool effect at the edge of the cliff, and two petrified rock waterfalls, imaginatively named “cascada chica” (small waterfall) and “cascada grande” (large waterfall), extending down the nearby cliff-face to the valley floor below.