Agua Azul

Blue Waters - Cascadas de Agua Azul - Cataratas de Agua Azul

Useful Information

Agua Azul, Chiapas. Public Domain.
Agua Azul, Chiapas. Public Domain.
Location: Cascada Agua Azul National Park. 50 km from Palenque, along Highway 199. Turnoff about halfway between Ocotsingo and Palenque. 200 km north of San Cristobal, past Ocosingo, on the way to Palenque.
Open: nor restrictions.
Best time APR to MAY.
Fee: free.
Classification: KarstSinter Terraces
Light: n/a
Dimension: L=6 km.
Guided tours: self guided
Photography: allowed
Accessibility: no
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


2017 water flow was drastically reduced by a new embankment of the river.


Agua Azul, Chiapas. Public Domain.
Agua Azul, Chiapas. Public Domain.

Agua Azul (Blue Water) is a series of shallow pools and waterfalls formed by rimstone dams. A 6 km long series of 500 waterfalls between 2 m amd 6 m high is partly open for the public. The central part of some 2 km of the pools are open to the public for walking along on trails, but also for swimming and bathing. The place is quite popular among locals and on weekends often crowded.

The limestone rich water of the Xanil river cascades down a series of rimstone dams around the Arroyo Agua Azul. During the dry season, in April or May, the water is shimmering turquoise blue because of the high amount of dissolved limestone. During the rainy season there is more water but it is not blue, the higher speed and energy of the water transports silt and sand which obfuscates the blue colour. The bright blue is a result of filtering sunlight by clear water. Water is transparent but light is nevertheless absorbed, but the blue parts of the spectrum are least absorbed. That's why water always has a blue color. But limestone rich water has a different kind of blue, because the different chemistry changes the optical properties of the water slightly. This is why so many karst related springs and rivers show exceptionally blue or turquoise colors.

The Xanil river is 30 km long and rises in the Chiapas Highlands and flows from Chiapas to the state of Tabasco. It was most likely named after the small village Xanil close to its spring, where the river is used as a balneario (spa). However, in its 30 km, only the area around Agua Azul shows rimstone pools. The dams are formed by the limestone in the water, the carbon dioxide is leaving the water or is consumed by plants, and as a result the dissolved limestone precipitates. The tiny calcite crystals in the water stick to the rim of the dam and the dam grows. The result are the typical bright white dams which contain a blue pool of water each. The interesting question here is, why does this happen only here?

The answer is simple, because the water becomes extremely limestone rich at the upper end of the rimstone pools. There is a karst spring in the river bed, which increases the amount of dissolved limestone substantially. In the central zone of the pools the river splits and flows downhill in four or five separate rivers. Here is the slope ideal for the formation of pools, not too steep, not too flat, and as the valley is wide the water flows calmer and has more time to deposit limestone.

The Arroyo Agua Azul is not only named after the pools, its economy is completely based on the tourists. There are dozens of restaurants and hundreds of souvenir shops and fast food venues. However, after you leave the village on the trail, the sound of the waterfalls dampens any other sound, and after only five minutes you feel like being alone. It also helps to visit the pools on weekdays.