Hierve el Agua is a set of mineral springs on a cliff edge about 70km east of Oaxaca city, and it is one of a very small number of places on Earth where carbonate-saturated water has built a formation that looks like a waterfall frozen in mid-fall. The name means the water boils, which it does not: the springs come out cold. What they do is deposit calcium carbonate, century after century, down a hundred metre rock face.
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What Is Here
THE WATER IS COLD AND THE NAME IS A MISTRANSLATION OF WHAT YOU SEE. The springs bubble up through the rock carrying dissolved calcium carbonate and magnesium, which makes them look as though they are simmering. They come out of the ground at roughly 22 to 25 degrees, which is pleasant rather than thermal, and the bubbling is gas escaping rather than heat.
THERE ARE TWO PETRIFIED FALLS AND THEY ARE DIFFERENT SIZES. The Cascada Chica, the small one, is the formation you walk out onto at the top, with the pools at its lip. The Cascada Grande, about 30 metres along the cliff and 12 storeys high, is the dramatic one, and it is best seen from the trail that drops below the rim rather than from the top.
THE POOLS AT THE TOP ARE THE REASON MOST PEOPLE COME, AND TWO OF THEM ARE ARTIFICIAL. The natural spring pools are small, shallow and protected. Alongside them sit built concrete pools fed by the same water, set right at the cliff edge so you swim towards a view over the valley. The image at the top of this post is that edge. It is a genuinely extraordinary place to be in water, and it is also crowded by eleven in the morning.
The second image shows what the formations are actually like underfoot. The travertine is rippled, porous, surprisingly sharp in places and slick where water runs over it. People walk out onto it barefoot and regret it.
THE SITE IS MANAGED BY THE COMMUNITY AND THAT MATTERS PRACTICALLY. Hierve el Agua sits on communal land belonging to San Lorenzo Albarradas, and access has been contested between neighbouring communities. THE SITE WAS CLOSED TO VISITORS FOR MORE THAN A YEAR, FROM 2021 INTO 2022, over exactly that dispute, and it has closed for shorter periods before and since. There is no national park service to appeal to and no advance ticket to hold. CHECK THAT IT IS OPEN WITHIN A DAY OR TWO OF GOING, through your accommodation in Oaxaca or a tour operator who runs it weekly, and have a second plan.
The third image is the travertine face from above, which is the only way to see the whole of what the minerals have built.
MOST PEOPLE ARRIVE AS PART OF A VALLEY CIRCUIT AND THAT IS THE RIGHT WAY TO DO IT. The standard eastern-valley day takes in El Tule, the enormous Montezuma cypress with the broadest trunk in the Americas; Teotitlan del Valle, where the wool rugs are woven and dyed with cochineal and indigo; Mitla, the Zapotec and Mixtec site with geometric stone mosaic walls unlike anything else in Mexico; a mezcal palenque, where agave is roasted in an earth pit and crushed under a stone wheel; and Hierve el Agua at the end. On Sundays the Tlacolula market, one of the great indigenous markets of the Americas, is on the same road.
There is a modest trail network at the site. A path descends from the rim to the base of the Cascada Grande and loops back up, taking about an hour, and it gives you the formations from below and a view back up the cliff. It is steep, loose and unshaded.
Food and facilities are basic and local. Comedores at the top sell tlayudas, quesadillas and cold drinks, there are changing rooms and toilets of a simple kind, and cash is expected throughout.
When to Go
October to April is the dry season and the best of it, with clear skies and warm days.
Arrive early. The site opens around eight, the tour groups out of Oaxaca reach it from about eleven, and the difference between half past eight and half past eleven at the pools is the difference between two trips.
May is the hottest month before the rains.
June to September is the rainy season, with heavy afternoon showers rather than all-day rain. The formations are more impressive when the springs are running strongly and the roads and the clifftop paths are less pleasant.
THE SPRINGS CAN RUN WEAK. Flow varies through the year and between years, and in a dry spell the water over the formations is a trickle. The rock is still there and still remarkable. Manage the expectation rather than being disappointed.
Getting There
Hierve el Agua is about 70km from Oaxaca city and takes between an hour and a half and two hours each way, because the last stretch is a narrow, steep, winding and partly unpaved mountain road.
By organised tour is how most visitors come, usually as part of the valley circuit, leaving Oaxaca around eight or nine.
By colectivo and camioneta, take a colectivo from Oaxaca to Mitla, then a shared pickup truck from Mitla up to the site, standing in the back for the last section. It is cheap, it is an experience, and the last trucks down leave in the late afternoon, so confirm the time before you go up.
By hire car is possible and the road is the reason to think twice, especially in the wet.
THERE IS AN ENTRANCE FEE AND IT IS COLLECTED IN STAGES IN CASH. Expect a community charge on the road in and a site admission at the top. Amounts are modest and change; cash in small pesos notes is the only thing that works.
Is Hierve el Agua Safe for Women?
Oaxaca is one of the more relaxed states in Mexico for visitors and the site itself is safe. The FCDO does publish advised-against areas for Mexico, and being precise about them matters more here than almost anywhere, because the country is large and the restrictions are specific rather than general. It advises against all but essential travel to the cities of Tijuana and Tecate in Baja California, to the areas of Guanajuato south-west of road 45D, to most of the state of Michoacan with named exceptions for Morelia and Patzcuaro reached by toll road, to the parts of Jalisco south and south-west of Lake Chapala and eleven northern municipalities, to the state of Colima except Manzanillo reached by air or sea, to the state of Guerrero except Zihuatanejo and Ixtapa reached by air, to a 40km strip of the Guatemalan border in Chiapas, to one stretch of Federal Highway 199, and to the city of Acapulco. That last one appears on the safety and security subpage rather than in the landing page list, which is exactly why you should read both. None of those areas includes this destination. Read the current advice yourself before you travel, because the list is revised regularly.
OAXACA STATE CARRIES NO FCDO ADVISED-AGAINST AREA AT ALL, and it is worth saying that plainly, because the Mexico advisory is long and a reader who skims it comes away with an impression that does not apply here. The restrictions named for Mexico concern Michoacan, Guerrero, Colima, Jalisco, Guanajuato, Tamaulipas, Sinaloa, Chihuahua and the border strips, not the Oaxaca valley.
THE CLIFF EDGE IS THE REAL HAZARD AND IT IS BARELY FENCED. The pools sit at the lip of a drop of tens of metres. There are low walls in places and nothing in others, the travertine is slippery wherever water moves across it, and people take photographs standing on wet mineral rock above a long fall. This is the thing that actually hurts visitors here.
The travertine will cut your feet. It is porous and sharp, and the walk between the changing rooms, the pools and the viewpoints is all on it.
You are at roughly 1,700 to 1,800 metres and the sun is fierce. There is almost no shade anywhere on the site and the pale rock reflects.
The descent trail to the Cascada Grande is loose and steep, and there is no barrier along the exposed stretches.
The road up is the statistically likeliest risk of the day, as it is on most mountain day trips in Mexico. Use a tour operator or driver with a sound vehicle, and avoid making the descent after dark.
The Hierve el Agua Packing List
Sharp wet rock, no shade, a long dusty road and water you will want to get into.
Our merino base layers are 100% Australian merino at 17.5 micron, and a long sleeve merino wool base layer for women is a better choice here than a cotton shirt for a specific reason: this is a day of strong high-altitude sun with no shade, you will be wet from the pools and then dry in the wind, and wool covers your arms and shoulders without becoming a cold damp layer the way cotton does.
A wide brim UPF 50 sun hat and a long sun hoodie for the time at the pools, where you cannot reapply sunscreen every twenty minutes and a cliff edge of pale rock reflects everything back at you.
Walking shoes with grip and Darn Tough merino socks for the descent trail and the valley circuit, which involves a lot of uneven ground at Mitla and El Tule as well.
A large insulated water bottle, because the comedores sell drinks but the altitude and the sun take more out of you than you expect, and a quick dry travel towel, since there is nowhere to hang anything and a cotton towel will be wet in your bag all afternoon.
Not linked and worth packing: SOMETHING ON YOUR FEET IN THE WATER. The travertine is sharp and slick and this is the single most useful item of the day, and we would normally link a water shoe here, but the only water-shoe entry in our affiliate register is unverified so we are giving the advice without a link rather than pointing you at something we cannot stand behind. Also A SWIMSUIT WORN UNDER YOUR CLOTHES, since the changing rooms are rudimentary; CASH IN SMALL NOTES for the two separate charges and the food; A DRY BAG OR PLASTIC BAG for the wet swimsuit; and SUNGLASSES, which the glare off pale rock and water makes genuinely necessary.
Recommended Tours and Experiences
Essential Resources for Women in Hierve el Agua
Emergency numbers: 911 for police, ambulance and fire, the single national number, free from any phone. English-speaking operators are available in the tourist states but are not guaranteed everywhere.
The one thing to do before you set out is confirm the site is open, because Hierve el Agua is on communal land, access has been contested between neighbouring communities, and it was closed to visitors for more than a year from 2021 into 2022 with shorter closures before and since. Ask your accommodation in Oaxaca or a tour operator who runs the trip weekly, within a day or two of going, and keep a second plan. THE POOLS SIT AT THE LIP OF A DROP OF TENS OF METRES and the barriers are partial, with slick travertine underfoot. THE ROCK IS SHARP AND POROUS and bare feet are a mistake. THERE IS NO SHADE and you are at around 1,750 metres. THE SPRINGS CAN RUN WEAK in a dry year. CASH ONLY, in small notes, for a community road charge and a separate site admission. THE LAST SHARED PICKUPS DOWN TO MITLA LEAVE IN THE LATE AFTERNOON, so confirm the time on arrival if you are travelling independently.
US State Department travel advisory: the Mexico advisory. Read the current level there directly rather than relying on a figure printed in any guide.
UK FCDO travel advice: gov.uk/foreign-travel-advice/mexico, and read the safety and security page rather than only the landing page, because that is where the substance sits.
Main hospital or clinic: there is no medical facility at the site and nothing substantial in San Lorenzo Albarradas. Mitla, about forty minutes down the mountain, has a small health centre. Anything serious means Oaxaca city, an hour and a half to two hours away, where there are both public hospitals and private clinics of a good standard. Private facilities expect payment or a direct insurance guarantee up front. Dial 911. Private hospitals in the large Mexican cities are good and expect payment or a direct insurance guarantee up front, so carry your policy number where you can reach it rather than in the bottom of a bag. Public clinics will treat an emergency. Tap water is not drinkable anywhere in the country: drink bottled or purified water, which every hotel and restaurant supplies as a matter of course, and take the same care with ice and raw salad that you would with the water itself.
Official health authority: the Secretaria de Salud, Mexico's federal health ministry. covers the Oaxaca state health services
US Embassy: the United States Embassy in Mexico City.
Official tourism authority: the Secretaria de Turismo, Mexico's federal tourism ministry. with state information from the Oaxaca tourism secretariat, which announces site closures when they happen
Takeaways
Check it is open before you travel. It has closed for a year before.
Be there by half past eight. By eleven it is a different place.
Put something on your feet. The rock is sharp and wet.
Walk down to the Cascada Grande. The big one cannot be seen from the top.
Solo women safety assessment: Hierve el Agua is an easy place to visit alone and the reason is that almost nobody visits it alone in the sense that matters: it is a day trip from Oaxaca, you arrive on a tour or in a shared pickup with other people, and the site itself is a busy, staffed, community-managed enclosure with comedores, changing rooms and a steady flow of visitors from mid-morning. Oaxaca state carries no FCDO advised-against designation at all, which is worth stating plainly because Mexico's advisory is long and specific and a reader who skims it will assume otherwise. Petty theft from bags left by the pools is the realistic crime risk, so nothing is left on a rock while you swim. 911 IS THE SINGLE NATIONAL EMERGENCY NUMBER, free from any phone, though English-speaking operators are not guaranteed outside the big tourist states. THE SERIOUS PRACTICAL POINT IS MEDICAL DISTANCE RATHER THAN CRIME: there is no clinic at the site, Mitla is forty minutes down a narrow mountain road and has only a health centre, and anything that needs a hospital means Oaxaca city an hour and a half or more away. That turns an ordinary injury into a long afternoon, and the injuries here are predictable. THE CLIFF EDGE IS WHAT HURTS PEOPLE. The pools are at the lip of a sheer drop, the barriers are low in places and absent in others, the mineral rock is slippery wherever water crosses it, and the photograph everyone wants is taken standing on exactly that surface. The travertine is also sharp enough to cut bare feet. Add high-altitude sun with no shade anywhere on the site, and the sensible version of this trip is grip on your feet, cover on your arms, water in your bag and a decision not to stand on the wet edge. FOR AN INDEPENDENT TRIP, the last shared pickups back down to Mitla go in the late afternoon: confirm the time when you arrive rather than assuming, because being stranded up there after dark is the one genuinely awkward outcome.
Reading On
Hierve el Agua is one stop on the eastern arm of the Oaxaca valley. The Oaxaca packing list covers the city you will base in, its markets and its mezcal, and the Monte Alban packing list covers the Zapotec capital on the ridge above it, which is the other great day trip from the same base. South over the sierra, the Mazunte packing list, Puerto Escondido packing list and Huatulco packing list cover the Oaxacan coast. Further afield, the San Cristobal de las Casas packing list and Palenque packing list cover Chiapas, the Puebla packing list and Mexico City packing list the route north, and the Merida packing list the Yucatan. For the country, the Mexico travel guide for women and the Mexico packing list carry the transport, the regions and the advisory geography in full. For why wool suits a day of strong sun and repeated soakings, read the guide to merino wool base layers for women. Every destination we cover is indexed at the travel packing guide for women, and the base layers are at the Roman Trail collection.
If the outer journey is calling you, the inner one usually is too. Explore SoulMap at romantrail.com/blogs/soulmap.
