tundrakurmitsa
New member
I have long wanted to see a lava tube because lava tubes are primary caves, and thus different from any other cave I have been in before. Our trip to Tenerife offered a chance, and it turned out that as we wanted something else than a tourist trip, Cueva de san Marcos on the northern coast of the island would be our best option. Many caves on Tenerife are gated, and Cueva del Viento, one of the biggest lava tubes in the world, is a tourist cave and thus not visitable by your own.
And to Cueva de San Marcos we went. The path to the cave was more demanding than the cave itself but nevertheless I liked our little caving trip. First we followed the cave to the other entrance, and found the geocache which is placed near that end. The other entrance is in the middle of thick vegetation, so we didn't try to go out. After that we took the left hand side passage near the entrance which leads further into the cave. After a short hands-and-knees crawl there was a pile of boulders where we had to climb up. After that we continued about 50 metres along the big passage. The air was warm and it felt very thick. Eventually we both noticed that we had started to feel unwell: we experienced a little shortness of breath, my partner got a headache, and I felt nauseous. That's where we decided to turn back, and when I was walking back towards the boulders, I noticed that my feet were shaking a little, and I really wanted to get back to better air. After we reached the boulders, it was easy to breathe again, and my nausea subsided. We also felt that it was colder under the boulders where the crawl starts.
This was the first time have experienced anything like that in a cave. I still don't know whether it was just CO2, or some gases produced by volcanic activity.
Anyway, we liked the cave because we haven't seen any primary caves before. It was also very useful to see what it feels like when there's bad air in a cave. At first it just felt a little warm there, and we didn't notice that something was wrong but as we continued walking, we realised that it didn't feel like as it should.
And to Cueva de San Marcos we went. The path to the cave was more demanding than the cave itself but nevertheless I liked our little caving trip. First we followed the cave to the other entrance, and found the geocache which is placed near that end. The other entrance is in the middle of thick vegetation, so we didn't try to go out. After that we took the left hand side passage near the entrance which leads further into the cave. After a short hands-and-knees crawl there was a pile of boulders where we had to climb up. After that we continued about 50 metres along the big passage. The air was warm and it felt very thick. Eventually we both noticed that we had started to feel unwell: we experienced a little shortness of breath, my partner got a headache, and I felt nauseous. That's where we decided to turn back, and when I was walking back towards the boulders, I noticed that my feet were shaking a little, and I really wanted to get back to better air. After we reached the boulders, it was easy to breathe again, and my nausea subsided. We also felt that it was colder under the boulders where the crawl starts.
This was the first time have experienced anything like that in a cave. I still don't know whether it was just CO2, or some gases produced by volcanic activity.
Anyway, we liked the cave because we haven't seen any primary caves before. It was also very useful to see what it feels like when there's bad air in a cave. At first it just felt a little warm there, and we didn't notice that something was wrong but as we continued walking, we realised that it didn't feel like as it should.