This cold wasteland is a volcanic treasure that has remained almost intact since the day it was formed, 27,000 years ago in Tenerife, as a result of one of the recurrent eruptions of the Pico Viejo volcanic complex. Its about largest volcanic tube in all of Europe and, thanks to its neat conservation, today it becomes a window to the future landscape of the west of La Palma, where its new volcano the morphology of the terrain continues to change.
Shortly after the lava stopped flowing, the grotto came alive. It is, in fact, the world’s most biodiverse location. More than 92 species of invertebrates coexist in it, of which 33 have always been living in the cave. They have adapted. They are born without eyes, but they are not blind, because they have never needed to see. Inside that gloomy grotto, they only need legs and antennae, with which they taste their prey or the sap of some root, as explained by the biologist and guide Francisco Mesa. Life in the cave goes at a different speed. So slowly that “the animals that live here live twice as long as if they did outside.”
The people of the island have also always adored the labyrinthine setting. The vast expanse of underground caves was used for a long time as a cellar or storage place. In fact, when the Tenerife Council He wanted to give it a new informative use, it took a whopping 24 years to get it ready. In addition to describing the safest areas for the public, conducting stability studies and establishing adequate measures to protect the habitat that had formed there; the truth is that they were forced to clean up. And it is that, it was then when they found that the settlers of the past had used certain places, such as the Sima de La Vieja, to get rid of their “agricultural garbage”, as Esther Martín, head of the Cave of the Wind Museum.
Some chroniclers have reported that these caves were even used by the aborigines in their funeral rites, although at the moment, it has not been possible to corroborate. “So far we have not found any mummy,” insists Martín. This, however, does not limit the possibilities of finding a Guanche body one day, since speleologists estimate that the Cueva del Viento can measure more than 75 kilometers, and today only 18.5 are known. “There are points where landslides originate and others are inscrutable,” admits Martín. This cave is made up of three tubes through which the hot lava flowed during various eruptive phases. The lavas were deposited on top of each other, and for this reason, there are holes as high as a building – due to the specific collapses during the eruption that formed cascades between the tubes – and others as tiny as a lizard.
For a volcanic tube to form, at least two circumstances must occur during the eruption: that the place where the lava passes has a steep slope and that the material expelled by the emitting center is very fluid. Once you have these ingredients, you just have to wait, because the volcanic tubes are formed “when the outside of the laundry cools and the lava continues to flow inside,” explains the head of the center. The creation of volcanic tubes is a fairly common phenomenon in Canarian volcanism. In the Archipelago there are several emblematic places that have this same origin. An example of this is the La Corona tunnel that flows into the Jameos del Agua, in Lanzarote, wave Cave of Las Palomas, in La Palma.
These structures are the ones that barely allow the lava flowing through the lava flows of the Palmero volcano to be appreciated. Most of the material is moving inside small volcanic tubes that open and close, collapse and overflow in the course of the eruption. When the Cumbre Vieja volcano ceases, it is possible that “few are left standing.” And, unlike the lavas that have formed the Cueva del Viento, which are cordate, those that are emanating from the La Palma volcano are badlands, much more prone to collapse. For this reason, in La Palma what there is usually “are small tubes of just 500 or 600 meters”, explains Martín. In fact, the only one that had this island so far is the Cueva de Las Palomas, which was formed in 1949 as a result of the San Juan eruption. In this case, the dimensions are around three meters wide by about 560 long.
Despite this, the scientific information it can provide is much greater than what existing tubes have provided so far. Once it can be visited, scientists will be able to learn how landslides occur, why there are areas with jameos – holes in the roof – or describe the colonization of new species. However, to start studying these new lava mazes you will have to spend a reasonable amount of time. Venturing to give a date is almost as risky as trying to predict the end of the eruption, but “it will take at least a year before you can access the tubes.” The new volcanic caves on La Palma will, however, have a much more important task. They must become living history that allows, as the Cueva del Viento does today, to remind canaries that the land they tread on is volcanic, with associated destruction, but with a future to admire..
Annual stability and radon studies
The majesty of the volcanic tubes makes them appear firm and solid. And they are, but they haven’t always been. Security is, therefore, the greatest obsession of scientists who daily make dozens of visits with groups of tourists or residents inside the Cueva del Viento. In addition to adorning visitors with construction helmets, scientists make regular reports on the cave’s stability. “During the formation of the tube there are many collapses, so you have to monitor it,” explains the head of the Museum, Esther Martín.
Just in the last few weeks, scientists have completed a millimeter stability study, based on a novel technique, with which they have discovered that there is little chance of collapses in the volcanic tube in the short term. In addition to conducting informative guided tours –whose places can be reserved on their website–, their work also consists of measuring annually the levels of radon that may be traveling through the volcanic tube. “This gas is harmful in large quantities and we are especially concerned about the exposure of workers,” insists Martín.
Fortunately, the volume of this gas contained in the tube is today derisory, so it has been concluded that there is no associated risk. In any case, the workers only venture once into the depths of the cave, whose entrance is protected by a small metal door. Both the stability measurement and the radon gas measurement are also carried out in the area that can be visited frequently by tourists to guarantee their safety at all times, and at the moment they are also being carried out in a deeper gallery that is not has opened to the public. “Our intention is to make it visitable at some point, but we want to do it well,” he remarks.
